Name:
Date:
Friday Quiz – Stoichiometry SCH4C
/20
1) How many grams of Ag will be produced from 1.23g of AgBr? Balance the equation first.
AgBr
Stoich-Ratio
m(g)

1.23
Ag
+
/5
Br2
?
mm(g/mol)
#mol
Final Answer:___________
2) If 7.11 x 1024 of silicon dioxide (SiO2) is used how many molecules of oxygen gas is required?
/5
2 Si2H2 +
3O2

4SiO2 +
H2O
Final Answer: ______________
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Date:
3) 15.00 g aluminum sulfide and 10.00 g water react until the limiting reagent is used up.
/5
(a) Which reactant is the limiting reagent?
(b) What is the mass of H2S which can be formed from these reagents?
(c) How many moles of the limiting reagent is remaining after the reaction is completed?
Al2S3
+
6H2O -
2Al(OH)3 +
3H2S
Final Answers:
a) The limiting reagent is______________________.
b) Mass of H2S is ________.
c) The limiting reagent is left with ________ moles.
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Date:
4) If 34.6 g of acetylene (C2H2) is used and 25.4g of oxygen gas is used.
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a) What is the limiting reagent? Final Answer:
b) How many grams of CO2 are produced? Final Answer:
c) How many moles of the excess reagent is leftover? Final Answer:
d) How many grams of the excess reactant is left after the reaction? Final Answer:
Hint: use #mol of limiting reagent to find b.
2C2H2
+
5O2

2H2O +
4CO2
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Name:
Date:
Bonus question: Explain using terms such as (LR, excess, reaction, mass, etc.) what happened in
the demonstration today with Aluminum and Copper (ii) Chloride.
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