Determination Of A Rate Law Essay

Determination of a Rate Law Essay
Determination of a Rate Law and Temperature Dependence of a Rate Constant
By Marvin Coleman
March 7, 2011
Abstract: From the shown calculations & graphical analysis, the experimentally determined rate law
is rate = K[I–].969 [H2O2].991 and the experimentally determined activation energy is 59.50
kJ/mole.
Introduction: The rate of a reaction varies at different temperatures and reactant concentrations. In
this experiment, the orders and dependence of the rate constant of the products used are determined
by the following chemical reaction:
2I– + H2O2–1 + 2H+ –> I2 + 2H2O–2
The general rate law for this reaction is: Rate = k [I–]x [H2O2–]y where k is the rate constant, x and
y are the orders, and the rate is equal to ... Show more content on Helpwriting.net ...
I2 + 2S2O3–2 –> 2I– + S4O6–2
.0001 moles S2O3–2 (1 mole I2)/ (2 moles S4O6–2) = .00005 moles I2 g. (.00005 moles I2 / .04 L)
/ 450 sec = 2.78 x 10–6 M I2/ sec h. log rate = log (2.78 x 10–6) = –5.56 i. M1 V1 = M2 V2
40 ml x = (2 ml) (.3 M) x = (2 ml/ 4 ml) (.3 M) = .015 M [I–] j. log [I] = log [.015] = –1.82 k. M1V1
= M2V2
(40mL)x = (6 mL) (.1 M) x = (6 mL) (.1M)/ (40 mL) x = .015 M H2O2 l. log [H2O2] = log [.015] =
–1.82
Results:
Cara and I were able to find that as the temperature increased, the faster the reaction took place. We
came to the conclusion that the experiment we were conducting was an endothermic reaction. We
were also able to conclude the rate order of the hydrogen peroxide and the iodine, which were both
first–order.
Discussion:
For the most part, the results turned out accurately. There were, however, several causes for
miscalculations. First, our measurements were not as exact as they should have been for several of

the experiments. Second, something went awry for trial 2, at least I believe, because our k value is
extremely high. Maintaining the correct temperatures for the experiments needing 30 and 40 degrees
was more difficult than expected, which is also likely to contribute in data not exactly comparable to
the predicted results.
Conclusion:
The slope of the line for Iodide at room temperature was: y = 0.969x + 3.6104 The slope for
hydrogen peroxide at room temperature was: y =
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Yeast Lab Report
Introduction: Enzymes are macromolecules that serve as a catalyst in a reaction. Catalysts are
substances that increase the rate of a chemical reaction without the enzyme being consumed by the
reaction (Reece et al. 2014). Reaction rate will increase if substrates bind to the surface of the
enzyme at a specific location known as the active site (Choinski and Karafit 2016). In this
experiment, we investigated the effect of pre–incubation temperature on catalase activity in baker's
yeast (Saccharomyces cerevisiae). Yeast is a eukaryotic organism very similar to our human cells
that is easy to control and can sustain a variety of environmental changes. Enzymes catalyze
chemical reactions by lowering its activation energy; enzymes lower activation ... Show more
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As pre–incubation temperature increased passed 30°C, catalase activity started decreasing at an
instant rate. Yeast pre–incubated in room temperature did not begin to denature; however, as pre–
incubation temperatures increased passed 30°C catalase activity instantly decreased. This immediate
decrease is perhaps due to the active site's change in shape which resulted in fewer substrates
binding to the active site causing enzymes to denature instantly, thus, resulting in less oxygen
liberated. A decrease in catalase activity could be caused by the denaturing of the hydrogen bonds
causing the enzyme to be less efficient resulting in the active site's inability to conduct the chemical

Activation Energy Barrier Lab
INTRODUCTION Most organisms rely on enzymes to digest their food. In all reactions, there is an
activation energy barrier. During digestion, foods must be broken down quickly so that the organism
can get the nutrients it needs. In order for the food to be broken down, the activation barrier must be
lowered. Without enzymes, many organisms would no longer be able to obtain the nutrients and
energy they need to live. In this experiment, the goal was to understand how and why enzymes work
in such specific ways, and to discover how enzymes function under different conditions. Without
enzymes, many reactions, including those that allow for the breakdown of the macromolecules that
we eat, could not take place. The activation energy would keep ... Show more content on
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This might slow down the process of pushing the oxygen gas into the graduated cylinder. This could
give the wrong data, showing instead of the correct time that the gas entered the reaction chamber at
a much slower speed than it should have been. This error could be eliminated by waiting to start the
timer until the first bubble of gas has left the tube. This would push all of the water out of the tube
before starting the data collection. Another error could be the solution not staying in the reaction
chamber. This could lead to unreliable data because there would be less solution. This could be
stopped by leaning the reaction chamber so that the tube is going straight up and therefore not
allowing any of the solution to escape. In Figure 1, the red line represents the second experiment. In
this experiment, some of the solution left the reaction chamber, and the timer was started as soon as
the tube was in the graduated cylinder instead of when the first bubble left the tube. There was less
gas by the end of 300 seconds than the first experiment (the blue line). This could mean that the
second experiment was not as reliable as the first as these errors were allowed to alter the

K-1andk1 Week 8
CHE341Homework Assignment #10Due:Monday16Novemberat6:00PM1.Aunimoleculargas–
phasereactionX→Yis activated with collisions by an unreactivecollision partner Bwith the following
mechanism:X+Bk1k−1⎯→⎯⎯←⎯⎯⎯X*+B,X*k2⎯→⎯Y,has a rate that follows the effective rate
equationdY[]dt=kuniX[]. (a) Apply the steady state approximation (SSA) to determine an
algebraicexpression forkuniin terms terms of the rate constantsk1,k–1andk2as well as [B].
(b)Discusshow the rate law changes in the limit of large and small [B].2.Dissociation of ethane into
methyl radicalsfollowsfirst–order kinetics with ArrheniusparametersA=2.50×1016s–
1andEa=367.6kJ mol–1. Calculate the Gibbs energy ofactivation, the entropy of activation and the
enthalpy of activation at500 K.3. ... Show more content on Helpwriting.net ...
(b) Calculate the initial rate of absorption ofC12H26Sfrom a 1 mM solution at 20 °C ifits initial
sticking coefficient is 1×10–6.6.A gas phase reaction between atomA and a diatomic molecule BC
has a positive activationenergy to reach a collinear transition state. Describe how the reaction to
form AB occurs.Suggest a plausible explanation for why the product AC is not formed.7.Calculate
thecollision rateof waterwith a surface ifthe surfaceis exposed to (a) water vaporwith a pressure of 1
atm and (b) liquid water?The system is held at 350 K.8.The forward and reverse rate constants have
been measured for the gas–phase reactionH2(g) +I2(g)2HI(g).The reaction is bimolecular in both
directions with Arrhenius parametersA=4.45×105dm3mol–1s–1,Ea=170.3kJ mol–1(forward
reaction)A'=5.79×101dm3mol–1s–1,Ea' =117.6kJ mol–1(reverse reaction)Computek,k' (rate
constant for the reverse reaction),K,ΔrG°,ΔrH°, andΔrS° at

Activation Energy For The Exergonic Reactions
According to the graph above, the activation energy for the exergonic reactions without a catalysis
enzyme is much higher opposed to the reaction with a catalysis enzyme; the free energy is constant
and doesn't change whether if there is a catalysis enzyme; the transition state differs because in an
exergonic reaction without a catalysis enzyme, it takes longer for the transition state to occur and
has a higher energy peak requirement while if there's a catalysis enzyme, then the transition state
occurs quicker and has a lower energy peak requirement. For the endergonic reactions, the reaction
without a catalysis enzyme has a higher activation energy requirement while the reaction with the
catalysis enzyme has a significantly lower ... Show more content on Helpwriting.net ...
How, specifically (4 ways) do enzymes speed up reactions and why are they more appropriate than
heat in living systems?
a. The four ways that enzymes speed up reactions and why are they are more appropriate than heat
in living systems are: active site template, active site stretch (induced fit), active site provides a
microenvironment and direct participation of the active site in the chemical reaction. For example,
each enzyme has its own specific active site that only allows specific types of substrates in and
allows for an enzyme–substrate complex; due to the creation of an enzyme–substrate complex, a
catalysis reaction is able to occur and speed up a reaction. The next enzyme mechanism is called
induced fit, and it is when an enzyme stretches a substrate molecule into a different and snug–fit
transition state which allows for the stressing and bending of critical chemical bonds eventually
leading to a catalysis reaction. The third enzyme mechanism is its ability to provide a
"microenvironment" or providing a suitable environment for a substrate to be in (acidic, neutral,
etc.) and is a key step in the formation of a catalysis reaction. The last and final mechanism of an
enzyme is its ability to directly participate in a chemical reaction through brief covalent bonding
between the substrate and side chain of an amino acid of an enzyme, which leads to a catalysis
reaction or a sped up reaction. These are all more appropriate than heat because if the

Chemical Kinetics: Enzymes Essay
Chemical Kinetics is the branch of chemistry that studies the speed at which a chemical reaction
occur and the factor that influence this speed. What is meant by the speed of a reaction is the rate at
which the concentrations of reactants and products change within a time period. Some reactions
occur almost instantaneously, while others take days or years. Chemical kinetics understanding I
used in the process of designing drugs, controlling pollution and the processing of food. Most of the
time chemical kinetics is used to speed or to increase the rate of a reaction rather than to maximize
the amount of product. The rate of a reaction is often expressed in terms of change in concentration
(Δ [ ]) per unit of time (Δ t). We can measure the ... Show more content on Helpwriting.net ...
An interesting result is obtained when the instantaneous rate of reaction is calculated at various
points along the curve in the graph of the change in concentration versus time. The rate of reaction
at every point on this curve is directly proportional to the concentration of the reactants at that
moment of time.
Rate = k(reactant concentration)
Because this equation is an experimental law that describes the rate of the reaction, it is called the
rate law for the reaction. The proportionality constant, k, is known as the rate constant. For general
reactions (aA + bB cC + dD) the rate law is (rate = k[A]x[B]y) where k is the rate constant and the
exponents x and y are numbers that must be establish experimentally. The values of the exponents in
the rate law indicate the order of the reaction with respect to each reactant. The sum of x and y is
called the overall reaction order.
Catalysts are one of the factors that extremely affect the rate of a reaction. Catalysts are substances
that speed up the rate of a reaction without being consumed themselves. When the reaction has
ended, you would have exactly the same mass of catalyst as you had at the beginning. One common
example are enzymes which are catalysts used to speed chemical reactions inside our body.
Enzymes bind for the time being to one or more of the reactants, substrate(s), of the reaction they

Photosynthesis Lab Report
Background Information:
Another word for enzymes is catalysts and most of them are proteins. They bind to the
substrates(reactants) temporarily of the very reaction that they catalyze. This speeds up the chemical
reaction because by doing this, the enzymes lower the amount of the activation energy required to
start the reaction. In the active site the the substrates are held by forces that are noncovalent who are
an assortment of hydrophobic reactions, hydrogen bonds, and ionic interactions. Most of these
interactions are weak and they are for sure weak if the atoms involved in the reaction are more than
one angstrom from each other. The temperature, pH level, enzymes concentration, and substrate
concentration can all affect the the enzymes. The spectrophotometer is an instrument used ... Show
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First, prepare a "blank" and for this you need to combine 2ml phosphate buffer, 1 ml 0.2% guaiacol,
2 ml 0.02% hydrogen peroxide, and 4 ml pH buffer all in a test tube of 13 times 100 mm. Using the
blank solution zero the spectrophotometer at 500 nm. Then prepare the three different series in the
13 times 100 m test tube and they will contain substrates and enzymes with buffers. Trial 1/ pH 4
consisted of pH 5 buffer(1 ml), 0.02% H202(2 ml), and 0.2% Guaiacol(1 ml) for substrate 1 while
enzyme 1 contains 2 ml of pH 5 buffer, 1 ml of enzyme extract, and 1 ml of phosphate buffer. Trial
2/pH 6 and Trial 3/pH 8 have the same procedure as Trial 1/pH 4. After all this is done, pour the
substrate for trial one into the Enzyme 1 tube. Start the timing right away. Then pour both of them
back into the tube that contained Substrate 1 originally and place that tube in the spectrophotometer.
Record the absorbance for every 20 seconds for 12 times. Then do these same steps for the other two
trials. Then graph your results. You do the same procedure for the other 2 pH

Does An Enzyme Specific Dose
Enzymes are proteins catalysts, in which the enzyme speeds up reactions. Enzymes speed up
reactions by lowering the activation energy. The enzyme or catalyst is not consumed in the reaction;
therefore, the enzyme can be reused (Areda, 2017). Activation energy is the energy needed to start a
chemical reaction (Reece, 2017). In other words, the activation energy is kind of like a barrier, in
which enzymes help decrease the amount of energy needed to start the chemical reactions. Enzymes
have unique shapes and one part of the enzyme that has a specific shape is the active site. The active
site is where the substrate (reactant) binds with the enzyme. When the enzyme and substrate attach
they form what is know as the enzyme–substrate complex. This

Enzyme Catalase Lab Report
Introduction:
A catalyst speeds up a reaction by lowering the activation energy that is used to start it. There are
both organic and inorganic catalysts–one being an enzyme. An enzyme is an organic catalyst that
speeds up the rate of a chemical reaction without being consumed by the reaction. Enzymes are
proteins, meaning that they have a unique structure that dictates what their function is. This unique
structure also determines what substrate, or specific reactant, the enzyme will catalyze. From there,
the substrate and enzyme bind together; which leads to the reactants being created.
The enzyme tested during this experiment was the enzyme catalase. This is an enzyme that is found
in both plant and animal cells, and is found in large ... Show more content on Helpwriting.net ...
As shown in figure 1: tube 1, the control group (with a plastic bead as the catalyst), did not have any
reaction. Tube 2 (containing the manganese dioxide as a catalyst), however, did have a reaction– its
rate was a 1 out of 4. Tubes 3 (with potato as the catalyst) and 4 (with liver as the catalyst) both had
bigger reactions, with tube 4 being the highest rating. Tube 3 was rated a 2 out of 4, and tube 4, with
the biggest reaction, was rated a 4 out of 4.
As exhibited in figure 2, tube 1 (with room temperature liver as the catalyst) was the biggest
reaction with a rate of 4 out of 4. Tube 2 (containing heated liver as the catalyst) did not have any
reaction, leading it to have a 0 out of 4 rating. The 3rd tube, containing cooled liver as the catalyst,
was the second biggest reaction with a rating of 3 out of 4. The last 2 tubes, 4 (with heated
manganese dioxide as the catalyst) and 5 (containing cooled manganese dioxide as the catalyst), had
very small reactions and were both rated 1 out of 4. Discussion/Conclusion
From this lab, I have discovered a lot of important information regarding enzymes and enzyme
function. For instance, during part 1 of the lab, I found out that manganese dioxide is not as effective
at catalyzing reactions than catalase is. This leads me to believe that enzymes as a whole are
sometimes more effective than non–organic catalysts. While the manganese dioxide created 2 cm
worth of bubbles, the

Enzyme Lab
Enzymes are proteins that catalyze (speed up) biological reactions in an organism by lowering the
activation energy of a reaction. They do this by either straining the bonds in a molecule so that is
easier to break up or by placing separate molecules/elements close to each other so that bonds are
formed. Enzyme activity is influenced by an array of different factors such as enzyme concentration,
substrate concentration, temperature, pH and inhibitor concentration. All of these affect the rate of
reactions of enzymes and some such as temperature, inhibitors and pH can under circumstances
cause enzymes to become permanently affected.
Catalase is an enzyme found in almost all organisms on earth exposed to Oxygen. It breaks down
H2O2, a dangerous ... Show more content on Helpwriting.net ...
Extension:
Comparing the trends shown in enzyme activity increase in catalase activity when no inhibitors are
added to when a set amount of competitive inhibitors are added and a set amount of non–
competitive inhibitors are added could extend this lab.
Another possible extension is comparing the efficiency of catalase to other peroxidases by
conducting the same experiment and seeing which enzyme will have the highest rate of reaction
overall.
Furthermore, one could compare the amount of catalase in an organism/part of an organism by
finding the rate of reaction of different origins of catalase under the exact same conditions with an
excess of hydrogen peroxide

Enzyme Lab
Abstract
Enzymes are organic catalysts that can help speed up chemical reactions (enzymes function p57).
There are very few exceptions, however all enzymes are proteins. Every enzyme is specific to a
certain chemical reaction depending on its substrate as well as amount (enzyme function p57).
Enzymes must maintain a specific structure so that they can work properly. If an enzyme's structure
is changed by chemicals or heat it may not be able to function at all.
Introduction
A metabolic reaction is any chemical change that occurs within a cell. Enzymes are proteins that are
used to speed up these reactions. The activity of these enzymes can be altered by changing their
environment, such as increasing and decreasing temperature and ... Show more content on
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For the next test the results were: in the incubator (37°C) had 75mm of bubble height. The test tube
that was in the ice bath (1°C) had the largest reaction with 80 mm of bubble height. The test tube
that was in boiling water (95/98°C)had no reaction. With these results we now know that our
hypothesis for temperature change was somewhat right. We said that by increasing the temperature
the catalase would begin to denature and have a very small reaction, which was correct. We also
guessed that the cold temperature would slow down or stop the reaction, which was incorrect.
For our next test we increased the amount of enzyme concentration, our results were as follows. Test
tube one was 1 cm to 5 cm with the bubble height measured at 0 mm. Test tube two bubble height
measured at 90 mm. Test tube three bubble height measured at 150 mm. We concluded that the
increase in concentration results in an increase of reaction. M hypothesis was

Enzyme Lab Report
Enzymes are catalytic proteins that accelerate the rate of biological reactions while experiencing no
permanent chemical modification as a result of their participation in a reaction. In order to initiate a
reaction from a reactant called a substrate to a product, a certain amount of energy, otherwise known
as the activation energy, is required. An enzyme functions by lowering the required activation
energy (which is usually provided by heat), thus, expediting the reaction. Many chemical reactions
happen very slowly, without the help of enzymes some reactions could take up to 3 billion years to
occur. Enzymes increase the rate of reactions by a factor up to 1017 times, allowing the chemical
reactions that make life possible to take place at ... Show more content on Helpwriting.net ...
Some enzymes, like the ones in your gut, break down large molecules into smaller ones, making
them easily absorbed by the body. Others, like the enzymes that make DNA, use small molecules to
build up large complex ones. Enzymes also help cells to communicate with each other, keeping cell
growth, life and death under control. The enzymes involved in respiration, photosynthesis and
protein synthesis work inside cells. Other enzymes are produced by specialized cells and released
from them. Different enzymes catalyse different digestion reactions. Amylase catalyses the
breakdown of starch into sugars in the mouth and small intestine. Amylase are produced in Salivary
glands, pancreas, and the small intestine. Proteases catalyse the breakdown of proteins into amino
acids in the stomach and small intestine. They are produced in the Stomach, pancreas, and small
intestine. Lipases catalyse the breakdown of fats and oils into fatty acids and glycerol in the small
intestine. Lipases are produced in the pancreas and small intestine. Three of the most common
enzymes are lipase that breaks down fats, protease that breaks down proteins, and carbohydrase that
work to breaks down

Enzyme Lab Report
Enzymes are catalysts (help process speed) for biochemical reactions. Enzymes are there to speed
up reactions by providing the reaction with an alternative reaction pathway of lower energy. Usually,
like all catalysts, enzymes always take part in the reaction, as that is how the enzymes provide an
alternative reaction pathway. The changes are temporary, so remain unchanged at the end of the
reaction. Enzymes are very selective of which reaction can go through, as to catalyzing specific
reactions only (M.J. Farabee, 2001). The uniqueness is due to the shapes of the enzymes. Most
enzymes are made of a protein and a non–protein, usually called a cofactor. The molecular bonds
that hold the proteins in their secondary and tertiary structures are ... Show more content on
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pH (Power of Hydrogen) is a scale that measures the acidity or basicness concentration in a solution.
..When the pH is in the range of below 7 (0–6), the solution is then said to be acidic; if the pH is 7,
the solution is then neutral. The pH is said to be basic if it is in the range above 7 (8–14). .As the pH
decreases, an enzyme will have the tendency to gain H+ ions, and through time, eventually enough
side chains of enzyme will be impacted, so that the enzyme's shape is changed causing the substrate
to not interact with the enzyme. .However, as the pH is increases, the enzyme will lose H+ ions and
lose its active shape. Though generally, biochemical reactions speed up as the temperature is
increased. ..As the temperature increases, the majority of the reacting molecules are now having
enough kinetic energy to go through with the chemical reaction. Enzymes are catalysts for
biochemical reactions, so enzyme reactions also move faster with increasing temperature (Indiana
edu., n.d) If the salt concentration of a molecule (Metal salt) is close to zero, the charged side chains
of amino acids of the enzyme (catalase) will attract each other and interact with each other. The
enzyme will eventually denature and form a precipitate that is currently inactive. If the salt
concentration is too high, the interaction of charged groups will be stopped and interfered with. New
interactions will eventually occur, and again the enzyme will produce a precipitate (Deakin
University,

Enzyme Controlled Reaction Lab
Title: Enzyme–Controlled Reactions
Enzymes catalyse reactions by lowering the activation energy necessary for a reaction to occur.
Enzymes are globular proteins that hasten chemical reactions. To catalyse means to speed things up
by acting as a catalyst. A catalyst is a substance that increases the rate of a chemical reaction without
undergoing a chemical change. The molecule that an enzyme acts on is called the substrate. During
the enzyme–catalysed reaction, the substrate is changed and a product is formed. Because the
enzyme remains unchanged it can continue to catalyse the same reaction multiple times. Each
enzyme is specific to the reaction it catalyses. When enzymes are folded, they create an area known
as the active site, the place that ... Show more content on Helpwriting.net ...
This is because the more neutral the pH the faster enzymes can catalyse reactions. If there is an
excess of H⁺ or OH⁻ ions then the shape of the protein alters, thus slowing down catalysis. The
graph shows this as pH7 is neutral and has the highest reaction rates, while pH3 and pH11, acidic
and basic, respectively, both have fairly low reaction rates. pH5 and pH9 are both in the middle
because they are slightly acidic, so they have a lower reaction rate than pH7, but a higher reaction
rate than pH3 and pH11.
Describe the relationship between substrate concentration and the initial reaction rate of an enzyme–
catalyzed reaction. Is this a linear relationship? What happens to the initial reaction rate as substrate
concentration increases? The relationship between each individual reaction is linear. As substrate
concentration increases the initial reaction rate increases fast at first, then slowly, then stays constant
from 4.0g of substrate to 8.0g of substrate.
What is the maximum initial reaction rate of this enzyme at pH7? The maximum initial reaction rate
of the enzyme at pH7 is 350 product molecules per

Does Amylase Affect The Rate Of Enzyme Activity
Introduction: Enzymes are biological catalysts that lower the activation energy required for a
reaction to take place. They speeds up the process of the reaction, while still not being consumed,
they can function multiple times. Enzymes are specific to molecules or sets of molecules and only
work with these specific substrates. The enzymes cause substrates to be converted to products faster
than they would without enzymes. A substrate fits into an enzyme, which then catalyzes the
conversion of the substrate into products. The enzyme facilitates reactions, however it can become
denatured. When an enzyme is denatured its form changes, thus preventing its function of
converting substrates to products faster, and the enzyme does not work. The enzyme used in this
experiment is amylase. Amylase is an enzyme that catalyzes the breakdown of the polysaccharide
starch into the disaccharide maltose. Amylase is produced by human salivary glands and aids in
digestion and breaking down food substances. ... Show more content on Helpwriting.net ...
The biological hypothesis is, temperature has an effect on the rate of starch digestion by the
amylase. The null hypothesis is, there is no significant change in amylase activity as the temperature
changes. Any deviations observed is due to chance. The alternative hypothesis is, there is a
significant change in amylase activity as the temperature changes and the temperature has
significant effect on amylase activity. The prediction is that temperature has a significant effect on
amylase activity and the null hypothesis will be rejected. This will be indicated by tube 2 showing
the most starch digested, which would be caused by the most enzyme

Enzyme Lab Report
Enzymes are catalysts that function to speed up reactions; for example, the enzyme sucrose speeds
up the hydrolysis of sucrose, which breaks down into glucose and fructose. They speed up reactions
but are not consumed by the reaction that is taking place. The most important of the enzyme is the
shape as it determines which type of reaction the enzyme speeds up. Enzymes work by
passing/lowering and energy barrier and in doing so; they need to bind to substrates via the active.
Once they do, the reaction speeds up so much more quickly than it would without the enzyme.
Coenzymes and cofactors aid the enzyme when it comes to binding with the substrate. They change
the shape of the active site so the substrate can bind properly and perform its function. ... Show more
Either pasteurized or raw milk is used to make cheese. When the cheese is made from raw milk, the
final product has different flavors and texture characteristics. The raw milk is always heated for a bit
in order to destroy any pathogenic organisms that could spoil the product and to give the cheese
cultures optimum condition. Pasteurized milk is pasteurized for the same reason. Cheeses like
cheddar or Swiss use the enzyme rennet in order to coagulate or clot the milk to form a curd. This is
why the cheeses that are made are so different from each other. As noted earlier rennet is obtained
from the stomach of ruminant mammals, mainly young calves and lambs. This is unfortunate
because these young mammals require this enzyme in order to digest their mother's milk. The
enzymes used in cheese production are quiet important to manufacturers. They provide different
aromas, textures and flavors according to the preferences of people. They also provide a longer shelf
life and are always aged for no less than 60 days. However, the continuous use of artificial enzymes
can reduce the amount of enzymes in your everyday diet. (Andrews, J,

Latas Latase Enzymes
Enzymes have several key parts to remember. In order for metabolism, which are all the chemical
reactions occurring in the body, to function properly; enzymes are there to assist (Shuster, 2012). All
enzymes are proteins that speed up metabolism (Shuster, 2012). Enzymes are catalysts. In order to
make reactions faster, enzymes bond to molecules in the reaction. They reduce the energy in
reactions in order to make them happen more often. There are two types of reactions. There is an
anabolic reaction, which builds up simple molecules making them into complex molecules. There
are also catabolic reactions, which break down the complex molecules making them into simple
molecules. Enzymes have a three–dimensional shape is also extremely important. Their shape is
determined by the order of amino acids that make it up (Brain, 2103). Every enzyme is specific and
will only catalyze one reaction (Shuster, 2012). If an enzyme can't distinguish between the substrate
and the phony molecule because of their structures, then it can lead to inhibition (Brain, 2013).
Denaturation could occur when anything changes such as the pH level, ionic strength, and the
temperature. Finally, it isn't impossible for reactions to occur without the help of enzymes. ... Show
It is found in the small intestine of mammals that catalyzes the breakdown of lactose, which is milk
sugar, into simple glucose(). Lactase is more present in humans during infancy. The main function
of lactase is to break down lactose. Lactose is found in milk and dairy products. One can be lactose
intolerant. Because lactose is a large sugar molecule, ones body cant break it down properly. These
people can take supplements to help them break down lactose in milk. Some people aren't able to
produce enough lactase for themselves. Being lactose intolerant, one can have stomach bloating,
nausea, abdominal cramps, diarrhea, and even having excessive stomach or intestinal

Determination of the Activation Energy of an Enzyme...
Determination of the activation energy of an enzyme catalysed reaction
Introduction
In this practical the aim for this experiment was to find out the catalytic power of alkaline
phosphate, as well as the rate of reaction and the activation energy of p–nitrophenol phosphate.
Enzymes are biological molecules that catalyse a chemical reaction. 'Enzymes work by lowering the
activation energy of a chemical reaction making it easier to proceed' [1]. This allows molecules to
have more energy therefore it makes them collide so that product can be formed much quicker. In
order for enzymes to work properly the activation energy must be exceeded first.
Enzymes are described as the lock and key complex. They have an active site which is ... Show
Samples at different incubation times (minutes) | Control 1 | Control 20 | 1 | 3 | 5 | 10 | 15 | 20 |
Absorbance | 0.006 | 0.009 | 0.030 | 0.058 | 0.174 | 0.414 | 0.568 | 0.593 | Concentration of nmol p–
nitrophenol phosphate/ml from the calibration curve | 0.50 | 0.59 | 2.00 | 3.50 | 9.50 | 24.50 | 35.00 |
37.00 |
Rate of reaction= Y2–Y1/X2–X1
10.5/5 =2.1 nmol p–nitrophenol/min/ml
Table showing the absorbance and concentration at 35 degrees centigrade for p–nitrophenyl
phosphate Samples at different incubation times (minutes) | Control 1 | Control 20 | 1 | 3 | 5 | 10 | 15 |
20 | Absorbance | 0.006 | 0.028 | 0.067 | 0.134 | 0.173 | 0.302 | 0.415 | 0.611 | Concentration of

Enzyme Lab Report
Background:
Enzymes, such as Catalase, are considered to be protein molecules in living cells. They are
implemented in the body to quicken the cells' chemical reaction speed by lessening the activation
energy. The activation energy is the amount of energy that is required to begin a chemical reaction.
This occurs when enzymes bind reactants and hold them in a certain position that increases the
likelihood that a desired chemical reaction will occur, causing the substrates to become products.
Similar to other catalysts, enzymes are not permanently changed in the chemical reaction that they
catalyze; enzymes revert back to their original forms at the end of the reaction. Their capability to
function as the catalysts depends on the protein's ... Show more content on Helpwriting.net ...
This is evidently depicted by the gradient of the graph sloping down. At this point, almost all of the
active sites are occupied, so the active sites are considered to be saturated with Hydrogen Peroxide.
Increasing the Hydrogen Peroxide Concentration after the point of saturation has been reached will
not result in the rate of reaction to go up even further. All the active sites are being utilized, so any
extra Hydrogen Peroxide molecules would have to wait until an active site becomes ready.
The theoretical maximum reaction rate is when all the sites are being actively implemented, but
realistically, this maximum is never reached. This is because not all the active sites are being
concurrently used all the time. The substrate molecules need time to bond to the enzyme and to
depart from it, so the maximum rate attained is always slightly below the theoretical maximum. The
time taken to move in and out of the active site is the limiting factor of the reaction rate.

Enzymes Lab Report
Enzymes are biological catalysts for speed up chemical reactions. They can be lowering its
activation energy to enhance reaction rate. Enzymes active site will only bind with certain substrates
for chemical reaction to occur.
In fact, almost all metabolic processes need enzymes for maintain fast rate for life in cell (Stryer L et
al., 2002). and, metabolic pathways are determined by the set of enzymes made. Enzymes can
catalyze > 5,000 biochemical reaction (Schomburg I et al., 2013). Different from all catalysts, they
can increase reaction rate by millions times by its specificity. Like orotidine 5'–phosphate
decarboxylase can speed up a reaction that that take millions of years to occur into only milliseconds
(Radzicka A st al., 1995). Specificity of enzymes come from their unique 3d structures. Enzyme are
protein that folded from many linear chain of amino acid. The sequence of the amino acids specifies
the structure which ... Show more content on Helpwriting.net ...
It is a sandwich enzyme immunoassay for the measurement of antibodies to hepatitis B surface
antigen. This technology is developed in 1970s. Here is using AUSZYME Monoclonal enzyme
immunoassay as example, it is a 2 steps assay. In the test the beads are coated with mouse
monoclonal Antibody to Hepatitis B. The sample blood is dilated and incubate at body temperature.
Any HBsAg present in sample serum would bound to the target antibody. Then after washing the
unbounded portion of sample, mouse monoclonal Anti–HBs conjugated with horseradish peroxidase
(Anti–HBs:HRPO) react with the antibody–antigen metioned above. Then again unbound portion is
washed out, o–Phenylenediamine (OPD) with hydrogen peroxide would add the beads to give a
yellow–orange color to show the portion with HBsAg. Then the mixture is tested by a
spectrophotometer with wavelength set at 492 nm to compare the absorbance with the control to see
if the HBsAg is

Factors Affect The Chemical Rate Of A Chemical Reaction
Introduction:
Enzymes are a protein that replicates a catalyst which helps chemical reactions begin to move
without the enzymes being changed in the process. Enzymes work to complete only one task. But
there are a variety of different enzymes in the body that each one has their specific task to complete.
Something that enzymes do is they are used in making foods, used for digestion. Many of the
chemical reactions in the body have a bunch of energy in them when they happen, which means it
can occur in a faster amount of time. Enzymes speed up a reaction by lowering the activation
energy. An inhibitor makes the reaction slow down. In this experiment we are testing how three
factors affect a chemical reaction. We will be representing different objects or materials as the
enzyme. We will use three objects or body part: a taped hand, a hand with a tennis ball in it, and a
rendered hand. The importance of this experiment is to see how three different elements affect the
chemical rate of a chemical reaction.
Materials and Method:
In this lab we needed supplies to help us conduct this experiment to make it successful. The
materials we used were 100 pennies, which represent the substrates. We also needed a hand to help
us represent the active site. The person in this experiment was the enzyme. The tennis ball in their
hand is represented by second enzyme we were testing. We used tape to help us with the third
enzyme trial. We used a stopwatch to help us record how long we had to

Enzyme Lab Report
Introduction
Background Information
An enzyme is a biological catalyst. This means that it speeds up the rates of reactions, particularly
those that are biological. The enzyme does not get used up in the reactions which it catalyzes.
Instead, it remains unchanged such that it can be reused in similar reactions in the future. Like most
other components in the body, enzymes are protein in nature. The nature of proteins is that they
operate under optimum conditions of temperature, pH and the concentration of the enzyme or
substrate. Above or below these conditions, the operation of an enzyme is affected. For instance,
below optimum temperatures, enzymes are inactivated. Denaturing occurs at temperatures higher
than the optimum temperatures. Denaturing is a permanent process and cannot be reversed by
lowering the temperatures (Stoker, 2012 p. 423). ... Show more content on Helpwriting.net ...
The pH scale is a scale used to measure the acidity or alkalinity of a substance. The scale is used
alongside indicators which act as the testers for the degree of acidity or alkalinity. It runs from one
to fourteen. Values below seven indicate acidity, while those above seven indicate alkalinity. At
seven, the substance is said to be neutral (Stoker, 2012 p. 423).
Question
The test question, in this case, is the effect of an acidic liquid on enzyme activity. In order to
complete this, it is necessary to understand that an acidic liquid has a pH value of below seven.
Hypothesis
Since the experiment is supposed to test the effect of an acidic fluid on enzymatic activity, the main
hypothesis will be along these lines. The hypothesis chosen here is that below the optimum pH of 7,
enzyme activity is reduced gradually.
Experiment Design
Materials
Plastic beakers or cups
Hydrogen peroxide

The Rate Of Catalase Enzyme Activity
The purpose of this experiment is to measure the rate of catalase enzyme activity under different
temperature conditions. The catalase enzyme is to be experimented on 4 different temperatures of
0oC,
23oC, 37oC, and 55oC, to determine which temperature has the fastest and slowest rate of enzyme
activity, Introduction
All organisms are made of the basic unit of life called cells. From bacteria to fish to plants to
humans, they are all supported by the cell theory. The cell theory "states that all living things are
composed of cells and that all cells come from other cells" (Reece, 2012). For these cells to
contribute to grow and function they must use the organelles and molecules accessible to them to
maintain sustainability.
Organelles like ribosomes and cytoplasm help with the cellular activity. There are also complex
molecules like nucleic acid and protein in which are important factors for organisms. These complex
macromolecules of our cells are rich in potential energy. Although rich in energy, complex
molecules do not spontaneously burst open. That reason being "there is an energy barrier that must
be overcome before a chemical reaction can begin" (Reece, 2012).
Thus where enzymes come in and play an important role in breaking down these complex molecules
or reactants. Enzymes speed up the cell's chemical reaction by lowering energy barriers. "Energy
must be absorbed to contort or weaken the bonds in reactant molecules so that they ca break and
new bonds can form"

Enzyme Lab Report
Enzymes are considered catalysts that speed up chemical reactions without being used in the
process. Enzymes react with substrates to form a temporary intermediary complex from which the
new product gets released. The enzyme that is unchanged and released at the end of the reaction will
be able to again combine with more substrate until all of the substrate is utilized. The enzymes in
living cells immensely accelerate chemical reactions and by governing relative reaction rates,
regulate the directions of metabolic change. Enzymes are greatly affected by changes in pH because
they are proteins. Every enzyme has a specific range for when pH will be the most active. This is
due to the effect of pH on a multitude of components: (1) the binding ... Show more content on
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Enzymes are complex molecular machines that deal with a broad array of chemical mechanisms.
According to Michaelis–Menten kinetics, enzyme–substrate reactions are composed of two
reactions. The first reaction occurs when the substrate forms a complex with the enzyme. The
second reaction utilizes the complex previously made to decompose into enzyme and product. When
the substrate concentration gets high enough to convert all of the enzyme to the complex form, the
second step of the reaction becomes the rate–limiting step. This entails that the overall conversion to
product becomes insensitive to further increases in substrate concentration. ("Enzyme Activity,"
n.d.). An essential part of an enzyme is the active site. The active site is where certain molecules
bind to the enzyme producing a reaction. If the shape of the active site is modified, the enzyme will
stop working. This relates back to pH affecting enzyme shape; enzymes only work at a specific pH
level ("Enzymes," 2014). Enzymes are held together by hydrogen bonds, so when an enzyme has
more H+ ions added to it, making it more acidic, the H–bonds get distorted and then

Enzyme Lab Report
Enzymes are biological catalysts, they have specific functions and structures that catalyze chemical
reactions within the body. Without the catalysing of these reactions, they would happen inefficiently
and too slowly to sustain life. (Science Museum, 2017) Each reaction needs small amounts of
energy to get started, this is known as activation energy. To start a chemical reaction, an enzyme
works by lowering the amount of activation energy needed.
Enzymes are proteins and are specific for their substrate, hence an amino acid substrate is formed.
Proteins are polymer molecules assembled by 20 different amino acid monomers. These protein
structures are critical for their functions and divided into primary, secondary, tertiary and quaternary
... Show more content on Helpwriting.net ...
This can affect the rate at which a chemical reaction occurs, this can also cause problems such as
alteration of the enzyme shape and causing the enzyme to denature. Factors that can implicate these
conditions of an enzyme are the increase or decrease of temperature or pH levels (Boundless, 2016),
presence of chemical inhibitors or presence of cofactors. As the temperature rises and reaction rate
rises within the body, any temperature above the optimum temperature of 37°C for catalase will
denature the enzyme by alteration of the active site and ruin the tertiary structure. The same effect
happens to the enzyme if the pH specific enzyme exceeds the level it works most efficiently at, most
working best at pH 7 (the exception of Trypsin of pH 8 and Pepsin of pH 2–3). Other factors that is
not impacted by the environment are inhibitors and cofactors, inhibitors have two categories,
competitive and noncompetitive. Competitive inhibitors bind to the active site preventing the
binding of substrates, noncompetitive inhibitors join another part of the enzyme and distort the
active site so that the substrate molecule is no longer complementary. Cofactors are required as they
loosely bind to a protein and are required for the proteins reaction to occur (Proprofs,

An Investigation Based On The Arrhenius Law
INTRODUCTION
This investigation is based on the Arrhenius law, A formula created by Professor Svante Arrhenius
that combines the Boltzmann distribution law with the concept of activation energy (Stephen Lower
2011a) to depict one of the most important relationships between temperature and rate of reaction in
chemistry to date. In the formula,
K = e ≈ 2.71828
A = Arrhenius' constant = Activation Energy
RT = Average kinetic energy (Universal gas constant × Temperature in Kelvins) In this experiment,
the main focus is placed on the Arrhenius plot, which is derived through the manipulation of the
Arrhenius equation to remove its exponential form by taking the natural log of both sides of the
equation which forms lnk=lnA–E_A/RT A ... Show more content on Helpwriting.net ...
This topic appealed to me, as it seemed like a sound concept in theory, but could not find any
discussion based on using the Arrhenius plot for physical processes.
BACKGROUND INFORMATION
2.1 Sublimation; an endothermic process
Sublimation is the term describing the transition of a substance from the solid phase to the gas phase
without passing through an intermediary liquid phase. (Anne Marie Helmenstine 2014a) It is a
physical change of state, which occurs at temperatures and pressures below the triple point of the
substance, the point where the temperature and pressure causes the 3 phases: solid, liquid and
vapour, of a single component system to be in equilibrium. (Blackwell Scientific Publications
Oxford 1997) This definition shows that sublimation is a purely physical process; so a substance
does not undergo a chemical reaction during sublimation.
This diagram represents a typical endothermic reaction: Fig. 2: Endothermic reaction enthalpy
change (hferrier n.d.)
As displayed in figure 2, a substance requires kinetic energy greater or equal to its activation energy
in order for it to change from its initial form to its product. The activation energy shown is one of
the pathways that a reaction takes with respect to the pressure that it is subjected to. Consider that
for a substance to change from its solid phase to its gas phase the bonds are all fixed in a position
and when the particles have enough energy, they are able to

The Rate Constants And Product Ratios
3.2 Rate Constants and Product Ratios
As mentioned above, the initial addition (CHClBr+NO2→ CHClBrNO2 a) is barrierless and
extremely exothermic. Considering the lower energy barriers for subsequent reactions, a, once
formed, will isomerize or dissociate to the products. The energy information in the initial addition
process is critically important for such case in the kinetic calculations. However, IRC calculation
can not be conducted for the barrierless reaction. Since the electronic interaction between C in
CHClBr and N in NO2 plays a significant role in this process, the energy profile of the association
can be obtained by the relaxed scan, in which the C–N distance in a is fixed from r=2.2 to 3.6 Å in a
step size of 1.0 Å and remaining geometries are optimized at B3LYP/6–31+G(d) level using tight
convergence criteria. Subsequently, CASPT2 method is utilized to calculate the single point
energies. Here, the energy of the reactants at r=10 Å are set to be zero for CASPT2 method. In order
to account for the dynamic electron correlation, the CASPT2(16,11)/aug–cc–pVTZ energies are
scaled by a factor of 1.18, corresponding to the ratio of the dissociation energies of a calculated at
CCSD(T)/6–311++G(d,p) level (–45.17 kcal/mol) and the CASPT2(16,11)/aug–cc–pVTZ level
(38.29 kcal/mol). Both of the results with ZPE correction are shown in Figure 3. Figure 3 confirmed
our assumption that a is formed barrierlessly via carbon–to–nitrogen approach. Based on the energy
information

Enzyme Lab Report
Essay 1: Enzymes have the capability to make specific reactions take place at a faster rate. This
means that enzymes are a catalyst, meaning that is speeds up reactions and is not consumed by the
reaction. Enzymes are good for cells because they do not require an increase of energy to make the
reaction happen. Amino acids make up enzymes, and all the amino acids are linked by peptide bonds
in a straight chain. This chain is called a polypeptide or protein. One example of an enzyme is a
hydrolases. A hydrolases works as a digestive enzyme, breaking down food into the nutrients and
elements we need. It works by breaking apart single bonds and adding in the element water. Another
enzyme is called a lyase. A lyase catalyzes the formation of double bonds, and does this by either
adding or subtracting chemicals. A third enzyme is a transferase, which aids in transferring
molecules to one another. Moreover, another enzyme is called an isomerase. An isomerase functions
by catalyzing the rearrangement of molecular structure. This works by breaking and forming bonds
to rearrange a molecule, while still keeps the same amount and type of atom.
Essay 2: ... Show more content on Helpwriting.net ...
These two cells are almost completely different in how they function and how they are made up. To
begin, prokaryotic cells are unicellular cells that lack internal organelles. These cells do not contain
a nucleus, instead they have what is called a nucleoid. A nucleoid is a single chromosome of DNA
that is found in the plasma of the cell. This DNA has a circular structure. Furthermore, prokaryotic
cells are, for the most part, bacterial cells. Some examples include streptococcus bacterium (the
strep throat virus) and Escherichia coli bacterium (which is found in warm–blooded organisms'

Comparing The Molecules In Two Interconvertible Conformation
If a molecule exists in two interconvertible conformations, both approximately equally populated, it
may show, depending on the frequency of interconversion, either the nuclear magnetic resonance
spectra corresponding to the individual conformations or an average spectrum of confirmations A
and B. If one has two conformations A and B in equilibrium in a substance and one heats the
substance until a given pair of resonance lines dues to A and B just coalesces (or if, originally, there
was only one set of lines, if one cools the substance until the resonance lines just begin to split), this
temperature is called the coalescence temperature Tc.2, 5 Molecules are in constant motion, and the
different conformations which are interconverted by bond

Potato Enzyme Lab
Enzymes Introduction An enzyme is a protein that acts as a catalyst. A catalyst speeds up chemical
reactions by breaking and forming bonds. To convert the substrate into the product an initial energy
is needed to contort the bonds so they may break. This energy is called the activation energy.
Activation energy is the amount of energy needed to begin the bond breaking process in a reaction.
Enzymes speed up reactions by lowering the energy barrier allowing reactions to progress. An
important property of enzymes is that although they can cause chemical changes in other molecules,
they are unchanged by the reaction. As a result, a single enzyme can catalyze the transformation of
many molecules. The purpose of this laboratory is to measure the ... Show more content on
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The wavelength of the spectrophotometer was set to 425nm. The catechol and the potato extract
were kept in test tubes on ice. The beakers were labeled waste, catechol waste, and potato extract
waste. Then, four test tubes were labeled and prepared for the potato dilutions. The first test tube
was filled with 5 ml of potato extract. The second test tube was filled with 2.5 ml of potato extract
and 2.5ml of H20. The third test tube was filled with 1.25ml of potato extract and 3.75 ml of h20.
The fourth test tube was filled with 0.625ml of potato extract and 4.35 ml of H20. These test tubes
were put aside. Four more empty test tubes were then prepared. One ml of catechol was added to
each of the four new test tubes. The first test tube containing catechol was filled with 4 ml of the
pure 5 ml potato extract. Directly after mixing the two together, 1 ml was pipetted into a cuvette and
entered into the spectrophotometer. A stop watch would then be set so the wavelength can be
recorded at specific times of 30 seconds, 60 seconds, 90 seconds and 120 seconds. These steps
would repeat for test tubes two through four. After these trials were complete, duplicates were
prepared following the same steps above beginning with the potato

Investigating The Rate Law And Activation Energy For 2hcl
The purpose of the experiment is to determine the rate law and activation energy for 2HCl(aq) +
Mg(s) → MgCl2(aq) + H2(g) as the form of magnesium used are magnesium strips. Inserting
magnesium strips to hydrochloric acid and evaluating the pressure of the reaction established the
rate law. The rate law was determined to be 4.77[Mg].767[HCl].864, which was established by the
data collected. By heating and cooling the hydrochloric acid and inserting the magnesium strip
allowed the evaluation of the pressure of the reaction and determined the activation energy. The
activation energy was determined to be 20 KJ/mol, indicating the reaction rate's sensitivity to
temperature. The reaction took longer due to magnesium strips surface area being larger than the
magnesium powder and magnesium shots. The experiments concluded that magnesium strips,
although surface area caused in increase in error, could produce accurate rate law and activation
energy in contrast to magnesium shots and magnesium powder.
Introduction
The purpose of the experiment is to evaluate the rate law result and the activation energy between
magnesium strips and hydrochloric acid. Many experiments and studies have been conducted in the
past to comprehend and use kinetics to evaluate the possibilities of understanding reactions. Kinetics
has the ability to keep human bodies functioning through reactions as well as contributing to the rate
of baking cookies to the rate of food spoilage in the bottom of

Chemical Kinetics Lab Report
Introduction
The principles of chemical kinetics is the study of reaction rates and the mechanism in a chemical
reaction.2 The rate of the chemical reaction can be represented as the change in concentration of a
solution with time. Also, the rate reaction can be express in an equation known as the rate law. The
rate law can be express as rate=f([A],[B],[C],...) (1) where the rate reaction is represented as a
function of the concentrations in the chemical equation with time.3 The general chemical reaction
can be shown as aA+bB→cC+dD (2)
Then using Eq. 2, to form the rate of consumption which is the reactant and the rate of formation is
the products
∂[D]/∂t=∂[C]/dt=–∂[A]/dt=–∂[B]/∂t (3) where the rate of reactant or product is instantaneous at a
given time.
The rate of the reaction can also be written using Eq. 1 as rate=k[A]^x [B]^y (4) where the
concentration are raised to a power are proportional and k is called the rate constant. The rate
constant is independent of the concentration but depend on the temperature.2 The exponents are
called the order of the reaction and the different type of order of reaction are determine by the sum
of the exponents.3 The first order rate law is shown as rate=k[A]^1=–∂[A]/∂t (5) using Eq. 3 an Eq.
4 and rearranging Eq. 5 to form
–∂[A]/[A] =k∂t (6)
Then integrating Eq. 6 at the initial time (t=0) for concentration of A to be [A]0 and [A]t at a later
time to form the limit of the integration for the first–order

Compare The Rate Of Reaction Between Crystal Violet And...
Discussion: In this experiment, the experimenters used spectrometry to study the rate of a chemical
reaction between crystal violet and sodium hydroxide to determine the rate constant and activation
energy, which is all dependent on the concentration of the reactants and temperature. Sodium
hydroxide was added to crystal violet, the indicator, to see how it changes with temperature. Sodium
hydroxide picks up H+ from the crystal violet and by experimenting in various temperatures from
approximately 25°C to 10°C, it is evident that temperature affects the rate constant. This reaction is
first order with respect to crystal violet, therefore by plotting the graph of ln absorbance versus time,
this appears evident. The rate constant at a temperature ... Show more content on Helpwriting.net ...
The amount measured are merely estimates, as there are always uncertainty of 0.2 mL, which is a
significant amount when dealing with small amounts of solution. Next, the rate constant at 40°C
would be 5.0152 s–1 by using the equation found in the graph of ln absorbance versus time:
y=3.2527(1/40) + 4.933 = 5.0152 s–1. Nevertheless, to the study the rate of the chemical reaction
and how it is affected by concentration of the reactants, the rate constant, and activation energy is
important. According to the chemist, Kim Davis, increasing the temperature increases the rate of the
reaction because by increasing the temperature of a system the average kinetic energy of its
constituent particles are increasing. As the average kinetic energy increases, the particles move
faster, collide more frequently, possessing greater energy when they collide, therefore increasing the
rate of the reaction. Moreover, concentration increases the rate of the reaction because the more
reactant particles that collide per unit of time, the more often a reaction can occur. As a result, this
experiment fostered knowledge on the relationships between the variables of the rate

Activation Energy
The experiment was interesting to say the least. There were errors involved and the calculations
don't seem 100% correct. Activation energy should have units of Joules only but when calculated the
activation energy, it had units of Joules per moles times seconds. There was probably and error in
the calculations or possibly just missing a step. There were also errors when recording time as the
lab manual was not followed correctly. Assuming that all experiments that took place were 1st order
reactions doesn't seem correct. R2 was higher compared to the 0th order but only barely and I was
unable to determine which was the correct order of the reaction. The results seem to make sense in
terms of activation energy. As temperature is being increased ... Show more content on
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There are a few reasons why HCl and MCAA are ran at different temperatures and different
concentrations. HCl is a strong acid while MCAA is considered a weak acid. They might have ran at
different temperatures due to their acidic strength and so the reaction and completely react. HCl is a
strong acid so it requires lower temperature compared to MCAA which needed higher temperatures
to completely react. The acidity between the two concentrations might also explain the difference in
concentrations between the two. It would be safe to assume that a strong acid would need lower
concentration. The reason why HCl is ran at 25℃ and 30℃ and MCAA is ran at 40℃ and 50℃.
HCl is ran at 25℃ and 30℃ because the chemical breakdown of sucrose at different temperatures
allows the formation of either glucose or fructose. As temperature increases, the sweetness the sugar
decreases and thus glucose would be favored. The lower temperature increases the sweetness of the
sugar and thus favoring the formation of fructose more. The reason why the rate of the reaction of
sucrose differs between HCl and MCAA is because water has a large excess amount that the
concentration of water doesn't change considerable. This means that when sucrose is chemically
broken down with a H+ (depending on which acid is being used) the reaction follows the equation
for a first–order reaction, even though there are

Enzyme Lab
Enzymes are large protein molecules that act as biological catalysts that aid in chemical reactions
that take place in living things. (Raven 44) Catalysts are substances that speed up the rate of
chemical reactions by decreasing the amount of energy needed for a chemical reaction to take place.
This energy barrier is otherwise known as the activation energy. Enzymes are one of the most
crucial facilitators of life in that they speed up reactions that would otherwise occur to slowly to
support life. (Perry 103)
The three–dimensional shape of these globular proteins allows them to act as a temporary stabilizer
of associations between the molecules that will undergo the reaction, or the substrates. (Raven 113)
The change of a substrate to a product requires overcoming the specific activation energy of the
chemical reaction. (Suzuki 3). Every enzyme has an active site, which is the site of the enzyme that
is crucial for enzyme activity. (3) The unique shape of the enzyme's active site causes enzymes to
have a certain aptitude for the particular substrate on which it acts on and subsequently for the
reaction it catalyzes. Once the reaction has occurred and the products are formed, the enzyme
molecules are ... Show more content on Helpwriting.net ...
(Raven 53) There are several factors that affect the ability of the enzyme to catalyze a reaction. In
this study, the effects of the substrate concentration, pH, and temperature will be examined. To test
the effects of these environmental factors on enzymes catalase, a common enzyme found in the
majority of all aerobic cells, will be examined. Catalase protects cells from the toxin hydrogen–
peroxide, which is a byproduct of cell metabolism by catalyzing the decomposition of hydrogen
peroxide into oxygen gas and water. The measure of oxygen gas and water under various conditions
is an indicator of the effects environmental factors have on enzyme activity. (German

Chemical Reaction Lab
In this laboratory the objectives were to understand the effects that temperature has on a reaction, be
able to calculate the reaction's rate constant, and to calculate the activations energy from the
recorded rate constant. Activation energy is the minimal amount of energy that is necessary to result
in a chemical reaction. With an insufficient amount of energy, a reaction won't occur, too much and
it will react just fine. A great example of this can be lighting a match. The friction created when
striking the tip covered in Potassium Chlorate against the match pad is enough energy for it to
ignite. Although, if there isn't enough kinetic energy from the swipe, than it won't ignite. The
activation energy in this lab was derived from the equation found from graphing the ln(k) and 1/T: ...
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The rate law is meant to display the relationship between the reaction rate and the concentration of
the various materials being used. Below is the equation that the was derived from in the reaction and
the rate law:
Balanced Equation: 6I–(aq) + BrO3–(aq) +6H+(aq) → 3I2 (aq) + Br–(aq) +3H2O
Rate Law: rate = k [I–][BrO3–][H+]2 The Arrhenius equation is used to graph the value found into a
relationship in order to determine the activation energy of the reaction. This equation can be easily
related to that of finding the slope of a line. The equation is given below and each components
definition: ln (k) = –(Ea/R) (1/T) + ln (A) y = mx + b k = Rate constant
T = Absolute temperature

Finding the Activation Energy Between Hydrochloric Acid an...
Finding the Activation Energy of the reaction between Hydrochloric Acid and Sodium Thiosulfate
The equation for the reaction is: S2O32– (aq) + 2H+(aq) ⋄ SO2 (g) + S(s) + H2O (l) Equipment – 2
boiling tubes – 400 cm3 beakers – Marker pen – Stand and clamp – Timer – Bunsen burner, tripod
and gauze – 0 – 100 oC thermometer – 2 x 10 cm3 measuring cylinders – Access to a fume
cupboard. Method 1. Label two boiling tubes A and B. Mark a dark spot on the side of a 400cm3
beaker, then ½ fill it with water. Clamp tube A and immerse in the water bath as shown in the
diagram above. 2. Using a measuring cylinder, transfer 10cm3 of sodium thiosulfate solution to tube
A. 3. Using a clean measuring cylinder, transfer 10cm3 of hydrochloric ... Show more content on
Helpwriting.net ...
| | |14 |1 |152 |152.33333333= |±2 | | | | |152 | | | |2 |152 | | | | |3 |153 | | | |34 |1 |59 |57 |±3 | | |2 |55 | | | | |3
|57 | | | |44 |1 |29 |29.3333333=29 |±2 | | |2 |29 | | | | |3 |30 |

Enzyme Activity Lab Report
pH, Temperature & Concentration on Enzyme Activity
Jazib Galani
April 27, 2017
Bio110
Professor Burkett
Community College of Baltimore County
Abstract
Enzymes are protein based biological catalysts which are responsible for majority of the biological
processes in a living organism. They are able to speed up catabolic and anabolic reactions without
being used up themselves, hence the term catalyst, and are very specific to the type of ssbtrate they
catabolize. Not only are they specific to the type of subtrate, but they operate under very particular
conditions, more specifically the pH of their environment, the temperature of the environment and
the concentration of the enzyme in question. In this particular experiment, the enzyme ... Show more
When discussing the availability and concentration of the enzyme, Table 1 and the subsequent graph
shows that as the concentration increases so does the rate of enzyme activity, meaning this is the
exception where there is no real optimum based on the parameters of the experiment. The second
variable, the pH, gives a slightly different result which is that the optimum pH is 7 based on the
slope of the top most line, compared to the other lines. The other lines prove that if the pH is not 7
the rate of activity would be lower. This result is unusual because, according to Moore, Powell, &
Goodwin (2008), "the optimum [pH] for activity[is] (5.75)" for the hydrogen peroxide catalyzing
enzyme. As for temperature, the enzyme seems to function well in the environment that mimics that
of the human body, meaning the optimum temperature is 37oC. The graph shows that any
temperature higher or lower than the optimum will yield a lower rate of activity, interestingly the
48oC line shows a spike in activity then an abrupt drop which may signify denaturing much like that
of the 100oC line. These experiments confirm the hypothesis that the enzyme would only function at
its peak level only when certain pH, temperature and

Determination Of A Rate Law Essay

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