Classic, mini chemistry experiments- some require materials typically found in a high school chemistry lab, while others are extremely simple. Very straightforward!
Classic, mini chemistry experiments- some require materials typically found in a high school chemistry lab, while others are extremely simple. Very straightforward!
Determination of the order of reaction between potassium persulphate & potass...PRAVIN SINGARE
This presentation is based on the experimental demonstration of "Determination of the order of reaction between potassium persulphate & potassium iodide by fractional change method". The presentation is for chemistry Undergraduate student of Mumbai University.
Classic, mini chemistry experiments- some require materials typically found in a high school chemistry lab, while others are extremely simple. Very straightforward!
Determination of the order of reaction between potassium persulphate & potass...PRAVIN SINGARE
This presentation is based on the experimental demonstration of "Determination of the order of reaction between potassium persulphate & potassium iodide by fractional change method". The presentation is for chemistry Undergraduate student of Mumbai University.
B. Pharm. (Honours) Part-IV Practical,Molecular biology & Biotechnology, MANIKImran Nur Manik
Molecular Biology & Biotechnology: (Marks –35)
a) Isolation of plasmid DNA
b) Estimation of DNA, RNA and oligonucleotides
c) Agarose-gel electrophoresis of nucleic acids
d) Determination of bacterial drug resistance by disk diffusion method.
e) Estimation of protein concentration by Lowry method
B. Pharm. (Honours) Part-IV Practical,Molecular biology & Biotechnology, MANIKImran Nur Manik
Molecular Biology & Biotechnology: (Marks –35)
a) Isolation of plasmid DNA
b) Estimation of DNA, RNA and oligonucleotides
c) Agarose-gel electrophoresis of nucleic acids
d) Determination of bacterial drug resistance by disk diffusion method.
e) Estimation of protein concentration by Lowry method
Classic, mini chemistry experiments- some require materials typically found in a high school chemistry lab, while others are extremely simple. Very straightforward!
Done By: khorg_Platinum Group
School Name: Al Khor Independent School for Girls
Environmental Catalysis Module: Students examines different types of catalytic systems, including heterogeneous and homogeneous catalysis. Depending on the knowledge they gained during activities, the students are then asked to design their projects.
Our Project:
Sulfur dioxide is converted to sulfuric acid,
phychem1phychem2Lab 9 Chemical Reactions IIPre-lab Qu.docxmattjtoni51554
phychem1phychem2
Lab 9: Chemical Reactions II
Pre-lab Questions
1. What is a limiting reagent?
2. A student used 7.15 g of CaCl2 and 9.25 g of K2CO3 to make CaCO3. The actual yield was 6.15 g of CaCO3. Calculate the limiting reagent and the percent yield.
Experiment: Synthesis of Garden Lime
Procedure
**Take photographs of your experiment set up and your results. Submit them with your laboratory report.**
1. Table 1 provides an example set of data for 1.0 g CaCl2.
2. For Trial 1, weigh into a 250 mL beaker the amount of calcium chloride (CaCl2) shown in Table 1. Record the exact mass you weigh out in the Trial 1 column of the Data section.
3. Measure 50.0 mL of distilled water into a 100 mL graduated cylinder. Pour the water into the 250 mL beaker with the calcium chloride.
4. Stir the solution with a stirring rod until all of the calcium chloride is dissolved.
5. Weigh out 2.5 g of potassium carbonate (K2CO3) in a 50 mL beaker. Record the exact mass in the Data section.
6. Measure 25.0 mL of distilled water into a 100 mL graduated cylinder. Add the water into the 50 mL beaker containing the potassium carbonate.
7. Stir the potassium carbonate in the distilled water with a stirring rod until it is all dissolved.
8. Pour the K2CO3 solution into the 250 mL beaker that has the CaCl2 solution. Rinse the beaker that contained the K2CO3 with a few mL of water and add this to the CaCl2 solution. Stir the mixture.
9. As soon as the reaction begins, record your observations in the Data section. Continue stirring until you see no more precipitate forming.
10. Set up the funnel in the Erlenmeyer flask as shown in Figure 2.
HINT: Do NOT begin filtering yet!
11. Zero the scale and weigh a piece of filter paper and a watch glass. Record the masses of both items in the Data section.
12. Prepare a filtering funnel as shown in Figure 2: fold a piece of filter paper in half twice to make quarters, and open the paper to make a small cone (three quarters are open on one side and one quarter is on the opposite side). Place the paper cone into the funnel and hold it in place with your fingers. Pour a small amount of distilled water through the paper to secure it inside the funnel.
13. Filter the mixture by pouring it into the filter paper in the funnel. Use the stirring rod and distilled water in a wash bottle to transfer the entire solid into the filter paper.
HINT: For best results, be sure to transfer all of the precipitate into the filter paper. Use a rubber policeman if it is available to help with the transfer.
14. Rinse the remaining solid in the filter paper twice with distilled water from a wash bottle to rinse off excess sodium chloride (NaCl). After all the liquid has filtered through, rinse the product with approximately 5 mL of ethanol to aid in its drying. Allow the ethanol to completely finish filtering through the paper.
15. Remove the filter paper carefully so as to not lose any product. Gently unfold the filter paper and lay it flat on t.
Lab 9 Chemical Reactions IIPre-lab Questions1. What is a limi.docxsmile790243
Lab 9: Chemical Reactions II
Pre-lab Questions
1. What is a limiting reagent?
2. A student used 7.15 g of CaCl2 and 9.25 g of K2CO3 to make CaCO3. The actual yield was 6.15 g of CaCO3. Calculate the limiting reagent and the percent yield.
Experiment: Synthesis of Garden Lime
Procedure
**Take photographs of your experiment set up and your results. Submit them with your laboratory report.**
1. Table 1 provides an example set of data for 1.0 g CaCl2.
2. For Trial 1, weigh into a 250 mL beaker the amount of calcium chloride (CaCl2) shown in Table 1. Record the exact mass you weigh out in the Trial 1 column of the Data section.
3. Measure 50.0 mL of distilled water into a 100 mL graduated cylinder. Pour the water into the 250 mL beaker with the calcium chloride.
4. Stir the solution with a stirring rod until all of the calcium chloride is dissolved.
5. Weigh out 2.5 g of potassium carbonate (K2CO3) in a 50 mL beaker. Record the exact mass in the Data section.
6. Measure 25.0 mL of distilled water into a 100 mL graduated cylinder. Add the water into the 50 mL beaker containing the potassium carbonate.
7. Stir the potassium carbonate in the distilled water with a stirring rod until it is all dissolved.
8. Pour the K2CO3 solution into the 250 mL beaker that has the CaCl2 solution. Rinse the beaker that contained the K2CO3 with a few mL of water and add this to the CaCl2 solution. Stir the mixture.
9. As soon as the reaction begins, record your observations in the Data section. Continue stirring until you see no more precipitate forming.
10. Set up the funnel in the Erlenmeyer flask as shown in Figure 2.
HINT: Do NOT begin filtering yet!
11. Zero the scale and weigh a piece of filter paper and a watch glass. Record the masses of both items in the Data section.
12. Prepare a filtering funnel as shown in Figure 2: fold a piece of filter paper in half twice to make quarters, and open the paper to make a small cone (three quarters are open on one side and one quarter is on the opposite side). Place the paper cone into the funnel and hold it in place with your fingers. Pour a small amount of distilled water through the paper to secure it inside the funnel.
13. Filter the mixture by pouring it into the filter paper in the funnel. Use the stirring rod and distilled water in a wash bottle to transfer the entire solid into the filter paper.
HINT: For best results, be sure to transfer all of the precipitate into the filter paper. Use a rubber policeman if it is available to help with the transfer.
14. Rinse the remaining solid in the filter paper twice with distilled water from a wash bottle to rinse off excess sodium chloride (NaCl). After all the liquid has filtered through, rinse the product with approximately 5 mL of ethanol to aid in its drying. Allow the ethanol to completely finish filtering through the paper.
15. Remove the filter paper carefully so as to not lose any product. Gently unfold the filter paper and lay it flat on the pre-weighed wat ...
Alpha Phi Omega - Its Founding and HistoryEmma Wise
Emma Wise, a graduate of Allegheny College, joined Alpha Phi Omega in 2009. Since that time, Emma Wise has completed numerous service projects both through the organization and on an individual level.
How to Contribute to the Midwest Food BankEmma Wise
Emma Wise volunteers with a variety of nonprofit organizations across the Midwest and in Pennsylvania, where she attended college. While volunteering with the Midwest Food Bank, Emma Wise helped service organizations connect with the food bank and obtain supplies during Distribution Weeks in 2012 and 2013.
Home Ownership through Habitat for HumanityEmma Wise
An avid community volunteer, Emma Wise has volunteered with the Geauga County chapter of Habitat for Humanity in Newbury, Ohio. There, Emma Wise partnered with organization leaders and other volunteers to build homes for families in need.
Fun lab on food energy! Calculating the number of ACTUAL calories in a cheese puff vs what it says on the package- includes pre-lab questions, procedure, data table, guided calculations, analytic/conclusion questions, percent error calculation, scaffolded summary of experiment to be filled in. Includes highlighted/filled in portions for teacher reference!
Chart depicting the electronegativity differences of atoms, including definitions and examples of ionic and covalent bonding in the context of electronegativity.
Wonderful visual activity for learning basic periodic trends- includes analytic and evaluative questions based on the activity, plus answer guide for teachers!
Great activity for solidifying understanding of protons, neutrons and electrons, with a bridge to interpreting atomic mass in the scope of isotopes. Note: you may substitute any materials you have on hand- toothpicks, marshmallows, other candy or craft supplies.
Thorough and exceptional list of strategies for reaching a wide range of student learners, but especially catering to those who require more challenge, as well as those who have requirements specified by IEPs (Individualized Learning Plans) .
Thorough and exceptional list of strategies for reaching all students, including those who are ESL or ELL (English as a Second Language or English Language Learners).
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
2024.06.01 Introducing a competency framework for languag learning materials ...
Simple Chemistry Experiments
1. Classic chemistry experiments
11
The preparation and
properties of oxygen
Introduction
Potassium manganate(VII) produces oxygen when heated. In this experiment oxygen is
produced and identified with a glowing splint.
Glowing splint
Ceramic wool
Potassium manganate(VII)
Bunsen burner
Heat-proof mat
What to record
What was done and what was observed.
What to do
1. Place two spatula measures of potassium manganate(VII) in a test-tube.
2. Place a small piece of ceramic wool near the top of the test-tube. This stops fine
dust escaping.
3. Gently heat the test-tube containing the potassium manganate(VII).
4. Light a splint and extinguish it, to make a ‘glowing splint’.
5. Place the glowing splint just above the top of the test-tube. Keep heating the testtube. The splint should relight.
6. Scrape out the ceramic wool. Let the test-tube cool to room temperature and then
wash it out.
7. Notice the colours produced when the test tube is washed out.
Safety
Wear eye protection.
Potassium manganate(VII) is harmful if swallowed. It assists fire.
Questions
1. What is the chemical formula for potassium manganate(VII)?
2. Classic chemistry experiments
12
Identifying polymers
Introduction
In this experiment solutions with known densities are used to identify the polymers
used in everyday materials.
Glass rod
Floaters
Test-tube
Samples
of plastic
containers
Sinkers
What to record
Solutions
Sample
Colour (or shape)
1
2
3
4
5
6
What to do
1. Fill six test-tubes with solutions 1 to 6 and label each tube.
2. Place a sample of each type of polymer into solution 1.
3. Use a glass rod to stir the contents of the tube. Observe whether the waste plastics
float or sink.
4. For samples that sink, write the letter S in column 1 of the results table.
5. Wash the glass rod and dry it on a tissue or paper towel.
6. Repeat the test for solutions 2 to 6. Use a new sample each time.
Safety
Wear eye protection.
Solutions 1,2 and 3 are highly flammable and toxic. Solutions 5 and 6 are irritants.
3. Classic chemistry experiments
Questions
1. Why were the solutions stirred once the plastics were added?
2. Use the following table to identify the plastics. Fill in the table.
Fingerprint
Polymer name
Acronym
Colour
1
2
3
4
5
6
Polyethylene
terephthalate
PET
Any
S
S
S
S
S
S
Polyvinyl chloride PVC
Any
S
S
S
S
S
–
Polystyrene
PS
Any
S
S
S
S
–
–
High density
polyethylene
HDPE
Any
S
S
S
-
–
–
Low density
polyethylene
LDPE
Any
S
S
–
-
–
–
Polypropylene
PP
Any
S
–
–
–
–
–
Expanded
polystyrene
EPS
Any
–
–
–
–
–
–
Polymer name
Acronym
Polyethylene terephthalate
PET
Polyvinyl chloride
PVC
Polystyrene
PS
High density polyethylene
HDPE
Low density polyethylene
LDPE
Polypropylene
PP
Expanded polystyrene
EPS
Sample
4. Classic chemistry experiments
13
Energy values of food
Introduction
In this experiment various foods are tested to find how much energy they contain.
Clamp
Test-tube
Water
Burning food
Needle
Wooden handle
What to record
Measurement
Food
Mass/g
Temperature of water
before heating/°C
Temperature of water
after heating/°C
Change in temperature/°C
Heat absorbed by water/J
(Temperature change x 4.2)
Heat absorbed by water
per gram of food/J
What to do
3
1. Put 10 cm of water in a test-tube. Clamp the test-tube in the retort stand at an
angle as shown in the diagram.
2. Weigh a small piece of food and record the mass in your table.
3. Take the temperature of the water in the test-tube and record it in the table.
4. Fix the food on the end of the mounted needle. If the food is likely to melt when
heated put it on a teaspoon instead of on the needle.
5. Light the food using a bunsen burner. As soon as the food is alight, hold it about 1
cm below the test-tube. If the flame goes out, quickly relight it.
6. When the food stops burning, stir the water in the test-tube with the thermometer
and note the temperature. Record it in your table.
3
7. Empty the test-tube and refill it with another 10 cm of water. Repeat the
experiment using a different food each time.
Safety
Wear eye protection.
5. Classic chemistry experiments
Questions
1. Suggest reasons why this experiment may not be a fair test?
2. Burning gives out heat. What is the name given to this sort of reaction?
3. The label on a packet of cheese says 100 g provides 1638 kJ. Calculate how many
joules this is per gram of cheese and compare it to the cheese in your experiment.
(1 kJ = 1000 J)
6. Classic chemistry experiments
14
A compound from
two elements
Introduction
A mixture of iron and sulfur can easily be separated. This is because there are no
chemical bonds between the sulfur and the iron. The iron is magnetic and is therefore
easily removed from the sulfur. In this experiment, a mixture of iron and sulfur are
heated to make a new compound.
Hold with tongs
Iron and sulfur
Bunsen burner
What to do
1. Examine the plastic bag of sulfur, the bag of iron and the bag containing a mixture
of the two.
2. Run a magnet over each of the bags.
3. Set up the apparatus as shown in the diagram.
4. Light a Bunsen burner and half open the air-hole to give a medium flame.
5. Heat the very end of the tube strongly. When the mixture starts to glow, move the
Bunsen burner to one side.
6. Watch the mixture in the tube. (If the glow just goes out, heat the tube again.)
7. Let the tube cool down completely.
8. The substance from the tube is a new compound called iron sulfide.
9. Test the iron sulfide with a magnet. Does the magnet pick it up?
Safety
Wear eye protection. Do not get too close to the fumes.
Questions
1. Write a word equation for this reaction.
2. What has happened to the iron and the sulfur in forming iron sulfide?
3. What is the chemical formula for iron sulfide?
7. Classic chemistry experiments
15
Chemistry and electricity
Introduction
In this experiment, electricity and some indicators are used to make coloured writing.
Filter paper soaked with
sodium chloride and
indicator solution
Petri dish
Positive terminal
Carbon electrode
Negative terminal
6V
Battery or
power pack
Lead
What to do
3
1. Dissolve a spatula measure of sodium chloride in 2 cm of water. Add three drops
of methyl orange indicator.
2. Lay a filter paper inside a plastic petri dish. Drop the solution onto the paper using
a dropping pipette, until the paper holds no more solution.
3. Attach the positive end of a 6 V battery to a lead ending in a crocodile clip. Use the
crocodile clip to grip one end of the paper.
4. Attach the negative end of the battery to a carbon electrode.
5. Write lightly on the wet paper, using the carbon electrode. What colour is the
writing?
6. Repeat the experiment using Universal Indicator. Describe what happens.
Safety
Wear eye protection.
Questions
1. What would happen if the lead were attached to the positive electrode using
Universal Indicator? Try this if there is time.
2. Explain what reactions have occurred to produce the colours.
8. Classic chemistry experiments
16
Combustion
Introduction
Hydrocarbons produce carbon dioxide and water when they burn. In this experiment
the products of combustion are captured and tested.
Gas jar
Candle
Tray
Heat-proof mat
What to record
What was done and what was observed.
What to do
1. Set up the apparatus as shown in the diagram. The gas jar should be placed over
the lit candle on a heatproof mat.
2. When the candle goes out, put a lid on the gas jar.
3. Test to see if the candle made water by adding a piece of blue cobalt chloride
paper, test the sides of the jar. If it turns pink, water is present.
4. Now test to see if carbon dioxide was produced. Pour a little limewater into the gas
jar. Swill it around a little. If carbon dioxide is present, the limewater turns cloudy.
Safety
Wear eye protection.
Questions
1. What is the gas that reacts with the hydrocarbon when it burns?
2. What gases does the candle produce when it burns?
3. Name another fuel that produces the same gases when it burns.
9. Classic chemistry experiments
17
The determination of
relative atomic mass
Introduction
One mole of any gas occupies the same volume when measured under the same
conditions of temperature and pressure. In this experiment, the number of moles of
hydrogen produced from a known mass of magnesium is measured. The relative
atomic mass of magnesium can therefore be calculated.
Magnesium ribbon
Burette
Dilute hydrochloric acid
Burette
Beaker
Magnesium ribbon
Water
What to record
The mass of magnesium used and the volume of hydrogen produced.
What to do
1. Clean a piece of magnesium ribbon (about 3.5 cm long) and weigh it accurately
(This should weigh between 0.02 g and 0.04 g; if not adjust the amount used.)
3
3
2. Measure 25 cm of dilute hydrochloric acid into the burette. Carefully add 25 cm
of water on top of this.
3. Push the magnesium in the end of the burette so it stays in position with its own
tension.
3
3
4. Add 50 cm of water to a 250 cm beaker.
5. Quickly invert the burette into the water, (if this is done quickly and carefully very
little will be lost. It is important that the liquid level in the burette starts on the
graduated scale. If it is not on the scale; momentarily open the tap, this allows the
level to drop).
6. Clamp the burette vertically.
7. Take a burette reading (NB: it is upside down!)
8. Observe how the magnesium reacts as the acid diffuses downwards, wait until all
the magnesium has reacted.
9. Note the new volume on the burette (NB: it is upside down).
10. Record your results.
10. Classic chemistry experiments
Safety
Wear eye protection.
Questions
The equation for the reaction is
Mg + 2HCl → MgCl2 + H2
1. Copy out and fill in the gaps:
3
____ g magnesium was produced from _____cm of hydrogen.
3
____ g magnesium was produced from 1 cm of hydrogen
3
____ g magnesium was produced from 24000 cm of hydrogen.
____ g magnesium would be produced from 1 mole of hydrogen.
This is the mass of 1 mole of magnesium. Numerically, this number is the relative
atomic mass of magnesium.
11. Classic chemistry experiments
18
The reaction of a
Group 7 element
(iodine with zinc)
Introduction
This experiment involves producing a salt by reacting a Group 7 element (iodine) with
zinc. This is an example of salt preparation by direct synthesis.
Filter paper
Filter funnel
Test-tube rack
Watch glass
Testtubes
Hot water from
kettle
Beaker
Iodine solution
and zinc
What to do
3
1. Use the measuring cylinder to add 4 cm of alcohol to a test-tube.
2. Dissolve a few crystals of iodine in the alcohol.
3. Note the temperature.
4. Add some powdered zinc (about the volume of a grain of rice) to the iodine
solution.
5. Stir with the thermometer and note the highest temperature.
6. Record any changes which suggest a chemical reaction has taken place.
7. Filter the liquid into another test-tube (the excess zinc is left behind).
8. Collect a beaker of hot water, and place a watch glass on the top
9. Pour the liquid filtrate onto the watch glass and allow the alcohol to evaporate.
Observe the product.
10. The product is classified as a SALT.
Safety
Wear eye protection. Do not touch the iodine.
Questions
1. What is the collective name for the Group 7 elements?
2. What does this name mean?
3. Complete the word equation:
Zinc + iodine →
12. Classic chemistry experiments
19
Reactions of halogens
Introduction
The Group 7 elements are called the halogens. This experiment involves some
reactions of the halogens.
Test-tube with
halogen solution
Glass stirring rod
Solution of halogen
Universal Indicator
paper
Tile
What to record
Complete the table.
Effect on
indicator
paper
Reaction with
potassium
chloride
solution
Reaction with
potassium
bromide
solution
Reaction with
potassium
iodide
solution
Chlorine water
Bromine water
Iodine water
What to do
1. Put a piece of Universal Indicator paper onto a white tile.
2. Use a glass stirring rod to transfer a few drops of the first solution onto the indicator
paper.
3. Repeat this with a fresh piece of paper and the different solutions.
4. In a test-tube, add some chlorine solution to a solution of potassium bromide.
5. Add some chlorine solution to a solution of potassium iodide.
6. Now try mixing solutions of bromine and potassium iodide. If there is time, mix the
other combinations of solutions to complete the table.
13. Classic chemistry experiments
Safety
Wear eye protection. Do not breathe chlorine gas.
Questions
1. Which halogen solution is the strongest bleaching agent?
2. Which halogen is the most reactive?
3. Write a word and symbol equation for the reaction of chlorine with potassium
bromide.
14. Classic chemistry experiments
20
The sublimation of
air freshener
Introduction
Sublimation is an interesting physical change. When a substance sublimes, it changes
directly from a solid to a gas without passing through the liquid state. Dry ice sublimes,
as do iodine and mothballs. This experiment involves the study of another common
substance that sublimes – air freshener.
Ice
LOOK HERE
Dish
Hot water
Piece of air freshener
What to do
3
1. Place a few lumps of air freshener in the bottom of the 100 cm beaker.
3
3
2. Put the 100 cm beaker carefully on top of the other 100 cm beaker.
3. Fill the top beaker three quarters full with ice. Ensure no ice enters the beaker
below.
4. Fill the shallow dish or pan about one-third full of hot water (at a higher
temperature than 45 °C).
5. Place the sublimation apparatus in the shallow dish in a fume cupboard.
6. Observe what happens to the solid. Be patient, it may take a while.
Safety
Wear eye protection. Use a fume cupboard.
Questions
1. What might be the significance of 45 °C? Try lower and higher temperatures if
there is time.
2. Define ‘sublimation’.
3. Use the particle theory of matter to explain what is happening and include a
particle diagram.