This document describes chemical reactions and equations. It discusses:
1. The components of chemical equations including reactants and products.
2. The different types of chemical equations including word equations, skeleton equations, and chemical equations.
3. How to balance chemical equations by ensuring equal numbers of each type of atom on both sides of the reaction arrow.
4. The five major types of chemical reactions - combination, decomposition, single replacement, double replacement, and combustion.
5. How to predict whether a precipitation reaction will occur based on solubility rules for ionic compounds.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Observation of Io’s Resurfacing via Plume Deposition Using Ground-based Adapt...Sérgio Sacani
Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
2. All chemical reactions…
Have two parts:
Reactants - the substances you start with.
Products - the substances you end up with.
The reactants turn into the products.
Reactants Products
A reaction can be described several ways:
In a word equation (some symbols used)
Copper + chlorine copper (II) chloride
2
3. To write a word equation, write the names of the
reactants to the left of the arrow separated by plus signs
and write the names of the products to the right of the
arrow separated by plus signs.
e.g. Hydrogen peroxide decomposes to form water and oxygen
gas.
Write the word equation of this reaction.
hydrogen peroxide Water + oxygen
(Reactants) (Products)
e.g. the burning of methane (combining with oxygen) produces
carbon dioxide and water. Write the word equation of this reaction.
Methane + oxygen carbon dioxide + water
(Reactants) (Products)
3
4. But it is easier to use the formulas for the
reactants and products to describe the chemical
reactions.
Chemical equation: is a representation of a
chemical reaction by using the formulas of the
reactants (on the left) followed by an arrow
then the formulas of the products (on the right).
4
6. ↓ used after a product indicates a solid has
been produced as precipitate: PbI2 ↓
↑ used after a product indicates a gas has
been produced (evolved) : H2 ↑
Catalyst: is a substance that speeds up the reaction
but is not used up in the reaction.
6
7. The Skeleton EquationThe Skeleton Equation
Uses formulas and symbols to describe a reaction but
doesn’t indicate the relative amounts of the reactants
and products.
All chemical equations are a description that describe
reactions.
Write a skeleton equation for:
1. Solid iron (III) sulfide reacts with gaseous hydrogen
chloride to form iron (III) chloride and hydrogen
sulfide gas.
2. Nitric acid dissolved in water reacts with solid sodium
carbonate to form liquid water and carbon dioxide gas
and sodium nitrate dissolved in water.
7
8. Write the word equation of the following:
Fe(s) + O2(g) Fe2O3(s)
Cu(s) + AgNO3(aq) Ag(s) + Cu(NO3)2(aq)
NO2 (g) N2(g) + O2(g)
8
9. Law of Conservation of MLaw of Conservation of Matteratter
A natural law describing the fact that matter is neither
created nor destroyed in any process
The amount of matter that you start with has to equal to
the amount of matter that you end with
Atoms can’t be created or destroyed in an ordinary
reaction:
All the number of atoms we start with ,
we must end up with
A balanced equation has the same number of each
element on both sides of the equation. 9
10. For Chemical Reactions This Means
• The amount of reactants
has to equal the amount
of products.
• Matter cannot be created
or destroyed through a
chemical reaction.
• Chemical equations have
to be balanced.
10
11. Rules for Balancing:Rules for Balancing:
1. Assemble the correct formulas for all the
reactants and products, use + and →
2. Count the number of atoms of each type
appearing on both sides
3. Balance the elements one at a time by
adding coefficients where needed (the
numbers in front) - save balancing the H
and O until LAST!
4. Check to make sure it is balanced.
11
12. Never change a subscript to balance an equation.
– If you change the formula you are describing
a different reaction.
H2O is a different compound than H2O2
Never put a coefficient in the middle of a formula
2NaCl is okay, but Na2Cl is not.
12
13. Balancing Chemical Equations
Example:
HCl + NaOH NaCl + H2O
H=2 H=2
Cl=1 Cl=1
Na=1 Na=1
O=1 O=1
The equation is balanced because the
number of atoms in the reactants are
equal to the number of atoms in the
products.
13
20. Types of Reactions
There are 5 major types of chemical reactions
1.Combination reaction or Synthesis reaction
2.Decomposition reaction
3.Single Replacement reaction
4.Double Replacement reaction
5.Combustion reaction
Not all reactions fit into only one category
Patterns of chemical reactions will help you predict
the products of the reaction 20
21. Combination Reactions
• Combine = put together
• 2 substances combine to make one compound.
Combination reaction: is a chemical change in
which two or more substances react to form a
single new substance.
• Ca +O2 → CaO (2 elements form 1 compound)
• SO3 + H2O → H2SO4 (2 compounds form another)
• When 2 non metals react (or a transition metal and
a non metal) in a combination reaction, often more
than one product is possible.
S(s) + O2 (g) → SO2 (g)
2S(s) + 3O2 (g) → 2SO3 (g)
21
22. Complete and balance
• Ca + Cl2 →
• Fe + O2 →
• Al + O2 →
• Remember that the first step is to write the correct
formulas – you can still change the subscripts at this
point, but not later!
• Then balance by using the coefficients only
22
23. #2 - Decomposition Reactions
• decompose = fall apart
• one reactant breaks apart into two
or more elements or compounds.
• NaCl Na + Cl2
• CaCO3 CaO + CO2
• Note that energy (heat, sunlight,
electricity, etc.) is usually required
electricity
→
∆
→
23
24. • Can predict the products if it is a
binary compound-Made up of only
two elements
– breaks apart into its elements:
• H2O
• HgO
electricity
→
∆
→
H2 + O2
Hg + O2
24
25. #3 - Single Replacement
• One element replaces another
• Reactants must be an element and a
compound.
• Products will be a different element and
a different compound.
• Na + KCl → No reaction
• F2 + LiCl → LiF + Cl2
25
26. • Metals replace other metals (and they
can also replace hydrogen)
• K + AlN →
• Zn + HCl →
• Think of water as: HOH
– Metals replace one of the H, and then
combine with the hydroxide.
• Na + HOH →
26
27. • We can even tell whether or not a single
replacement reaction will happen:
– Some chemicals are more “active” than
others
– More active replaces less active
• There is a list on page 333 - called the
Activity Series of Metals
Higher on the list replaces lower
27
28. The Activity Series of the Metals
Lithium
Potassium
Calcium
Sodium
Magnesium
Aluminum
Zinc
Chromium
Iron
Nickel
Lead
HydrogenHydrogen
Bismuth
Copper
Mercury
Silver
Platinum
Gold
• Group 1, 2, & 3 Metals are
more active than Hydrogen
and any other metals
(transition metals).
So Group 1, 2, & 3 Metals can
replace Hydrogen and any
other metals (transition
metals).
Higher
activity
Lower
activity
28
30. The Activity Series of the Halogens
Fluorine
Chlorine
Bromine
Iodine
Halogens can replace other
halogens in compounds,
provided that they are above the
halogen that they are trying to
replace.
2NaCl(s) + F2(g) 2NaF(s) + Cl2(g)
MgCl2(s) + Br2(g) ???No ReactionNo Reaction
???
Higher Activity
Lower Activity
30
31. #4 - Double Replacement
• Two things replace each other.
–Reactants must be two ionic compounds
–Usually in aqueous solution
• NaOH + FeCl3 → ???
–The positive ions change place.
• NaOH + FeCl3 → Fe+3
OH-
+ Na+1
Cl-1
• NaOH + FeCl3 → Fe(OH)3 + NaCl
31
32. Complete and balance:
• assume all of the following
reactions actually take place:
CaCl2 + NaOH
CuCl2 + K2S
KOH + Fe(NO3)3
(NH4)2SO4 + BaF2
32
34. #5 - Combustion
• Means “add oxygen”
• Normally, a compound composed of only C,
H, (and maybe O) is reacted with oxygen –
usually called “burning”
• If the combustion is complete, the products
will be CO2 and H2O
• If the combustion is incomplete, the products
will be CO (or possibly just C) and H2O.
34
36. SUMMARY: an equation...
• Describes a reaction
• Must be balanced in order to follow the
Law of Conservation of Mass
• Can only be balanced by changing the
coefficients.
• Has special symbols to indicate
physical state, if a catalyst or energy is
required, etc.
36
37. How to Recognize which type:
Look at the reactants:
A + B = AB (Combination)
AB = A + B (Decomposition)
A + BC = AC + B (Single replacement)
AB + CD = AD + CB (Double replacement)
A + O2 = (Combustion)
37
40. Predicting the formation of a precipitate
Some combination of solutions produce precipitates,
while others do not, whether or not a precipitate forms
depends upon the solubility of the new compounds that
form.
You can predict the formation of a precipitate by
using the general rules for solubility of ionic
compounds.
These rules are shown in the following table:
40
41. Solubility Rules for Ionic Compounds
Compounds Solubility
Sodium, potassium, and ammonium salts Soluble
All nitrates and chlorates salts Soluble
All chlorides except silver chloride and
lead chloride
Soluble
All sulfates except, silver sulfate, lead
sulfate, and barium sulfate
Soluble
All carbonates, phosphates, hydroxides,
sulfides and chromates salts except with
sodium, potassium and ammonium
Insoluble
Insoluble salt = Precipitate
41