Why does the solution divide by two in Mole Stoichiometry?

In summary, the conversation is discussing a solution for a chemistry problem where the individual followed the steps shown in the provided picture. The question is why the person divided by 2 in the calculation for the weight, when typically mole to gram conversions are done as a 1 to 1 ratio. The expert explains that dividing by 2 again makes the molecule appear lighter than it actually is and should not have been done.
  • #1
Homework Statement
79. Chlorine gas reacts with fluorine gas to form chlorine trifluoride.
Cl2( g) + 3 F2( g) = 2 ClF3( g)
A 2.00-L reaction vessel, initially at 298 K, contains chlorine gas at a partial pressure of 337 mmHg and fluorine gas at a partial pressure of 729 mmHg. Identify the limiting reactant and determine the theoretical yield of ClF3 in grams.
Relevant Equations
R= gas constant
n= moles
T = temperature in kelvins
So essentially I followed pretty much what is in the picture
here in this solution.


My question is essentially why does he do the 0.07XXX mol f2 * 2mol clf3/3mol f2 * 92xx g/2mol f2 = answerfor the weight. I always thought as the mole to grams as a 1 for 1 sort of deal. That is if something has a mass of 95.45 amus that means that 1 mole weighs ~ 95.45 grams. However, he divided by 2 again where one would normally not because you are essentially dividing mass per mol by 2, making the molecule lighter than it really is.


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  • #2
They should not have divided by two.

Related to Why does the solution divide by two in Mole Stoichiometry?

What is mole stoichiometry?

Mole stoichiometry is a branch of chemistry that deals with the quantitative relationships between reactants and products in a chemical reaction. It involves using the mole concept to calculate the amount of reactants needed or products formed in a chemical reaction.

How do you calculate moles?

To calculate moles, you can use the formula: moles = mass/molar mass. This involves dividing the given mass of a substance by its molar mass, which is the mass of one mole of the substance.

What is the mole ratio in stoichiometry?

The mole ratio in stoichiometry refers to the ratio of the number of moles of one substance to the number of moles of another substance in a balanced chemical equation. It is used to determine the relative amounts of reactants and products in a chemical reaction.

How do you use mole stoichiometry to solve problems?

To solve problems using mole stoichiometry, you first need to write a balanced chemical equation for the reaction. Then, determine the given and desired quantities, and use mole ratios to convert between moles of different substances. Finally, multiply the moles by the molar mass to convert to grams if needed.

What are some common sources of error in mole stoichiometry calculations?

Some common sources of error in mole stoichiometry calculations include errors in measurement, incomplete reactions, and impure reactants. It is important to use accurate and precise measurements and ensure all reactions are complete and all reactants are pure to minimize these errors.

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