This document provides instructions and questions about mole ratios and calculations involving chemical equations. Students are asked to write conversion factors between elements in compounds, calculate moles of one substance given moles of another in a balanced equation, list mole ratios, and determine unknown quantities of substances using balanced chemical equations and moles of given substances.

1. Moles and Mole Ratios (DO NOT WRITE ON)
Answer each of the following questions using the equation provided. MAKE SURE TO
BALANCE EACH EQUATION BEFORE SOLVING ANY PROBLEMS. SHOW ALL WORK!
1. Write three conversion factors that relate the moles of elements present in the
compound Al2S3. (ex:2 mole Al= 1 mole Al2S3.)
2. How many moles of Al are in 1.26 mol of Al2S3?
Use the following balanced equation for questions 3 & 4…
Al2(SO4)3 (aq) + 3 Ba(NO3)2 (aq) →3 BaSO4 (s) + 2 Al(NO3)3 (aq)
3. List the six possible mole ratios from this reaction.
4. What are two things that the coefficients can represent?
5. For the reaction: NO + O2 → NO2
a. 2 moles of NO will react with ______ mole(s) of O2 to produce ______
mole(s) of NO2.
b. How many moles of NO are needed to react with 6.3 moles of oxygen?
c. How many moles of NO must react to form 3.67 moles of NO2?
6. Write and balance the reaction between calcium metal and nitrogen gas to
form calcium nitride.
a. Write the three possible mole ratios for this reaction.
b. The coefficients don’t represent mass directly. What masses of each
reactant and product would be needed to make this reaction true? (show
your work)
c. If 35.9 moles of calcium were used up in this reaction, how many moles of
nitrogen gas would also have to be used up?
Herrera April 2012