Questions tagged [stoichiometry]
Stoichiometry refers to the relationship between the amounts of substances of the reactants and the amount of substances of the formed products. This tag should be used for specific questions about chemical reaction equations.
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How to track dependent reactions or reactants using stoichiometric matrix of metabolic system
I am modeling a metabolic network of signaling pathways through a system of ordinary differential equations
$$
\frac{dX}{dt} = F(X) = S v
$$
where $X$ is the vector of molecules (121 in my case) ...
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Stoichiometry problem with copper coin with mass 5.00 g. After some time, the coin is removed and its mass is 6.41 g [closed]
A copper coin of mass 5.00 g is immersed in a silver nitrate solution where the reaction proceeds:
Cu + 2AgNO3 → Cu(NO3)2 + 2Ag
After some time, the coin is removed and its mass is 6.41 g. Determine
...
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On Concordant Readings in Titrations
In titrations like acid-base($\ce{NaOH}$ and $\ce{(COOH)2}$) and redox($\ce{KMnO4}$ vs Mohr's Salt), why do we use the concordant volume(mode) of the solution whose molarity is to be determined rather ...
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1g=.602x10(23) amu?
1) 6.02 x 10 (23) amu is same as 6.02 x 10 (23) atoms?
1 mole is 6.02 x 10 (23). It can be atoms or molecules or particles regardless of atoms gram like 12 bananas is dozen regardless 12 bananas ...
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Magnesium Bicarbonate Synthesis, How to be Certain of the Moles of CO2 added to Water?
Background Research
Through googling all I find is using chilled sparkling water or carbonating water and then adding a teaspoon of magnesium hydroxide to it.
The problem with these methods is that ...
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Are individual reaction rates of reactant dependent on stoichiometry in non elementary reactions?
For the complex reaction with stoichiometry $\ce{A + 3B->2R + P}$ and with second order rate expression: $r_P=kC_AC_B$ are the reaction rates related by $r_A= r_B =r_R =r_P$? If the rates are not ...
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Concentration and Chemical reaction
When two reactants partially react, and we are asked about concentration of one reactant, should we consider the volume of reactants, or if the products?
Here's an question to make it clear.
How much ...
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Proceeding of chemical reaction and stoichiometry
Suppose two reactants react to form more than one product depending upon the quantities taken. So I assumed that one of the reactant will become limiting reagent, another reactant remains unreacted, ...
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Stoichiometry of Neutralisation Reaction
For the following question, though the answers are available on web, none of them are providing exact reason behind WHY the specific formula was used.
Question -
What Volume (in $\pu{mL}$) of $\pu{0.2 ...
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Stoichiometry of gaseous mixture of CO CO2 and N2
I am confused about the following question which is mostly about reduction of volume in reactions along with stoichiometry and gaseous mixtures. The question is as follows:
200ml of a gaseous mixture ...
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Balancing of a chemical reaction of oxidation of sulfides by ozone
My textbook mentions the following reaction:
$\ce{MS(s) + 4 O3(g) -> MSO4(s) + 4 O2}$ (where $\ce{M}$ = $\ce{Pb}$, $\ce{Cu}$, $\ce{Zn}$, $\ce{Cd}$)
$\ce{PbS(s) + 4 O3(g) -> PbSO4(s) + 4 O2}$
...
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Iterative mixing problem
This is a very math-heavy problem from the Chemistry Olympiad:
Beakers P and Q are placed side by side. Initially, P contains 100 cm³ of 1.00 M Na⁺ solution, while Q contains the same volume of 1.00 ...
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What is the difference of "limiting reactant" and "limiting reagent"?
I am doing a problem that has its answers stated separately for a) and b). One says that $X$ is a limiting reagent and one says $Y$ is a limiting reactant.
My question is, is there a difference ...
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Correct reaction for formation of magnesium pyrophosphate
I found the following reaction for formation of magnesium pyrophosphate:
$$\ce{H2PO4 + Mg^2+ + NH4 -> Mg(NH4)PO4.6H2O ->[\Delta] Mg2P2O7},$$
but its stoichiometry looks incorrect, as well as ...
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Fuel Rich combustion
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A fuel rich mixture of certain Hydro-Carbon fuel C12H24 and oxygen (O2) at standard condition, is burnt at a mixture ratio 2.5. Assuming initially all the H is oxidized to H2O and thereafter ...
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Why should the pH change when I add sodium hydroxide to water? [closed]
I am a student and I am trying to understand the concept of pH.
If I add pure $\ce{NaOH}$ in water, it leads to the formation of $\ce{OH-}$ ions in the water. But this shouldn't lead to any change in ...
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Net concentration of sodium hydroxide after addition of phenol red indicator
I am planning to use an acid-base reaction with an indicator for some flow studies. I will be using aqueous solutions of sodium hydroxide (NaOH) and hydrochloric acid (HCl) with phenol red as the ...
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How do these two definitions apply to the same term?
Tushar's answer to this question (What is an equivalent?) gives two definitions for an "equivalent"
An equivalent (symbol: officially equiv; unofficially but often Eq) is the amount of a ...
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Percentage Yield
For the above MCQ question, I took the equation to be
$$\ce{CaC2 + 2H2O -> C2H2 + Ca(OH)2}$$
I then calculated the moles of $\ce{CaC2}$ as 0.7273 moles, which has a 1:1 molar ratio to $\ce{C2H2}$, ...
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Removing glass fiber from samples before mass spect run?
I would like some unbiased opinions and knowledge from you all if you have time. I am measuring Phosphorus content of snail and embryo samples. I am only interested in Phosphorous content. I ...
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Use of Equivalent in organic chemistry
The question is taken from an engineering entrance exam in India(JEE 2024)
If 3 mole of aniline is reacted with one equivalent of benzene diazonium chloride the maximum amount of aniline yellow formed ...
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Different method of solving a question giving different answer [closed]
Calculate the concentration of nitric acid in moles per litre in a sample which has a density, $\pu{1.41 gmL^–1}$ and the mass per cent of nitric acid in it being $69 %$.
I attempted to consider a 1L ...
user142438
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Law of multiple proportion fitting in the notion of an atom
I have been reading about atoms. Currently, I am referring to the book "Atom : Journey across the subatomic cosmos" by Issac Asmov.
I believed that if we start dividing something so we can ...
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Model EC50/Kd values using ordinary differential equations
It is my first attempt at using ordinary differential equations to model Kd for antibody binding and help will be much appreciated.
To provide some context, I possess binding curve data for the EC50 ...
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Is it not possible to balance the equation $\ce{I2 +O3 -> I4O9 +O2}$ in many ways? [closed]
The above reaction can be balanced in many ways. For example, the coefficient of $\ce{I2}$ is two when coefficient of $\ce{I4O9}$ is one. But the coefficient of $\ce{O3}$ and $\ce{O2}$ can be 5 and 3 ...
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How do I calculate the fuel consumption inside a cylinder-piston stoichiometrically?
Consider I have car 4-cylinders with total cylinder capacity is 1,496cc. Per piston, the cylinder is 374cc. The piston diameter is 72.5mm, height=90.6mm, and compression ratio is 11.5:1. Hence we may ...
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Does a chemical reaction depends on the amount of reactants?
A chemical reaction depends on many things like the temperature, pressure etc. i wanted to ask if It also depends on the amount of reactants for example;
If A + B gives C and assuming this equation is ...
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Can I reuse LDPE bottles after trace element analysis?
I run some algae samples through mass spec a few times over the month to test the P content of algal samples. My (simplified) procedure was as follows:
Put a small portion of algae in a teflon vessel
...
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How to find the formula of a binary compound if we know the mass of solid product and the volume of escaped gas?
During the decomposition of a binary compound two simple substances
were formed: 44.8 grams of metal and 47.04 liters of a non-flammable
gas (conditions are normal). Find chemical formula of the ...
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Parentheses use in non stoichiometric compounds
When should one use (or not) parentheses in writing the formula for non stoichiometric compounds.
I mean, the mineral sphalerite is often represented by the formula $\ce{(Zn,Fe)S}$ and, all though I ...
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Calculation of the retained mass after hydrolysis of an oligopeptide
I would like to ask about a problem that I am stuck on:
An oligopeptide is made up of glycine, alanine, and valine. Hydrolysis of X in $\pu{500 mL}$ of $\pu{1 M}$ $\ce{H2SO4}$ solution yields ...
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How to calculate carbon to phosphorus stoichiometric ratios using results from ICP-MS and CHN analyzer?
I run a few chemostats to manipulate the carbon to phosphorus ratio (C:P) of algae, which is later feed to an invertebrate. I used Inductively coupled plasma mass spectrometry (ICP-MS) and Inductively ...
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What is the meaning of "maximum" weight produced after series ot reactions?
$4.14$ grams of a piece of lead was made to react with $\ce{HNO3}$ so as to produce lead nitrate. Lead nitrate further reacts with a series of reagents to form $\ce{(NH4)2PbCl6}$. Then find the ...
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What are some efficient approaches for balancing long chemical equations? [closed]
I am having some difficulties in balancing chemical equations involving many elements. It takes a lot of time (for me) to balance the coefficients using the hit and trial method. Especially like this ...
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A reaction based question from stoichiometry [closed]
A 110.0g sample of a mixture of CaCl2 and NaCl is treated with Na2CO3 to precipitate the Calcium as Calcium Carbonate. This CaCO3 is heated to convert all the Calcium into CaO and the final mass of ...
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Why is Fe3O4 a non-stoichiometric compound? [closed]
Fe combines with O in a whole number ratio 3:2. Even the ions Fe2+ and Fe3+ are in the ratio 1:2. Then, why Fe3O4 is a non-stoichiometric compound?
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How would you find the Q value in the Nernst equation if you were to change the temperature?
I'm studying how changing the temperature of the anode would affect the voltage produced within a galvanic cell. I think that the Nernst equation plays a role here but I am unsure how the reaction ...
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Finding the molecular formula given combustion data
$\pu{150 cm^3}$ of oxygen were added to $\pu{20 cm^3}$ of a gaseous hydrocarbon D.
After explosion and cooling, the gaseous mixture occupied $\pu{130 cm^3}$
and, after absorption by potassium ...
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Calculate volume of hydrogen gas evolved
MCQ Question:
Ammonia borane in water can release hydrogen upon hydrolysis while forming NH4BO2 as the other
product.
The volume (cm3) of hydrogen gas which will be evolved from the hydrolysis of 309 ...
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Finding concentration of ascorbic acid
Question:
A person applied following procedure for the determination of ascorbic acid (Vitamin C) in a sample solution.
A volume of 20.00 cm3 of the ascorbic acid sample was reacted with 25.00 cm3 of ...
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UV absorbance titration to determine binding stoichiometry
I previously posted a question but I think I did not explain correctly. I want to construct a Job plot using UV-Vis titration to find binding stoichiometry. I have 20uM of ligand solution and 20uM of ...
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Find percentage of carbon monoxide reacted using ideal gas equation
Question
A palladium or platinum catalyst was used in an automobile to convert carbon monoxide gas to carbon dioxide according to the following reaction:
$$\ce{2CO(g) + O2(g) -> 2CO2(g)}$$
A ...
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Calculating required mass of reactant to produce a specific product
I want to know how many grams of $\ce{C}$ (carbon) are required to create $\pu{58 grams}$ of $\ce{Na2S}$, given
$$\ce{Na2SO4 + 2C -> Na2S + 2CO2}.$$
First I calculated molecular mass of $\ce{Na2S}$ ...
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What is mol % and how do you calculate the mass of a compound needed to be a certain mol % relative to another compound at a particular volume? [closed]
I know that there is some stoichiometry involved, but I am lost here. I know you need the molecular weight of both compounds and that's about it?
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Find the added volume of HCl so that the ions separate
Suppose we have a 10mL solution that contains 0.02M $\ce{Ag^+}$ and 0.04M $\ce{Ba^{2+}}$. a) Find the necessary volume to be added of $\ce{HCl}$ to separate all the silver. (Assume to be separated if ...
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Does stoichiometric gas mixture produce the highest explosion pressure (or energy) compared with other explosive limit mixture?
I understand that a stoichiometric mixture contains a balanced mixture of air and fuel and both fuel and air are completed consumed. For example, the ideal stoichiometric mixture for propane is ...
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What's the stoichiometric ratio of Kerosene to a mixture of 50% water and 50% hydrogen peroxide [closed]
So I'm wanting to do some testing with combustion of certain liquids, and I'd like to know what the right ratio is for these liquids. What I'm going to be using is regular kerosene (NOT RP-1) and 50% ...
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Find the required water volume to add so that the pH of two solutions will be the same
Question.
We have two flasks: one contains 50 mL of 0.001 M HCl and the other 50 mL of 1M acetic acid.
a) How much water should be added to the more acidic solution so that the pH of the two ...
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Store Palladium Chloride in Solution
I have one gram of palladium chloride ($\ce{PdCl2}$) and I want to use very small quantities of it, in milligrams somewhere. It is not possible for me to get my hands on a scale that can measure that ...
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What is the difference between a single displacement reaction and a two competing reaction system?
For example, consider the single-displacement reaction
$$\ce{AB + C <=> BC + A}$$
My question is then if writing this reaction as the system
\begin{gather}
\ce{AB <=> A + B} \\
\ce{B + C &...
