3rd Nine-Weeks
Week # 08
Honors Chemistry
CW 15: Stoichiometry – Practice Test
Name: _________________________________________ Date: ________ Period: _________
You must show the work that leads to your answer in order to receive credit. The answer must be
rounded to the appropriate significant digits and with the appropriate unit.
1.
______________(a) How many grams of carbon dioxide are produced when 25.0 g of
aluminum carbonate is heated? [14.1 g CO2]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(b) What is the percent yield if the reaction produced 11.4 grams of
carbon dioxide? [80.9%]
______________(c) How many moles of aluminum oxide are produced from the decomposition of
25.0 g of aluminum carbonate? [0.107 moles Al2O3]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
2.
______________(a) How many grams of 2,3 – dimethyl butane will react with 7.5 moles of oxygen gas?
The reaction is a complete combustion reaction. [68.1 g C6H14]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(b) How many grams of water are produced when 7.5 moles of oxygen
gas react with 2,3-dimethyl butane? [99.6 g H2O]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(c) If the percent yield is 88.6 %, how many grams of water were
actually produced? [88.2 g H2O]
3.
______________(a) How many grams of iron are produced when 4.25 g of magnesium
react with iron (III) sulfate? [6.51 g Fe]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(b) If the experiment produced 6.17 g of iron, what is the percent
yield? [94.8 %]
______________(c) How many grams of iron (III) sulfate are needed to react with
the 4.25 g of magnesium? [23.3 g Fe2(SO4)3]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
4.
______________(a) How many grams of water are needed to react with 40.8 g of
tetraphosphorus decoxide? The only product formed is phosphoric acid.
[15.5 g H2O]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(b) How many grams of phosphoric acid are produced when 40.8 g of
tetraphosphorus decoxide reacts with the water? [56.3 g H3PO4]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(c) What is the percent yield of the experiment if 52.5 g of
phosphoric acid was produced? [93.3 %]
5.
______________(a) How many grams of lead (II) acetate react with 8.37 g of lithium phosphate?
[35.3 g Pb(C2H3O2)2]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(b) How many grams of precipitate are produced when the 8.37 g of
lithium phosphate react with the lead (II) acetate? [29.3 g Pb3(PO4)2]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________(c) If the experiment produced 25.5 g of this product, what is the
percent yield? [87.0%]
______________6. How many grams of magnesium metal are required to react with
4.75 mL of hydrochloric acid? The density of hydrochloric acid
is 1.35 g/mL. [2.14 g Mg]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________7. Brass is 35% zinc. How many grams of iron (III) nitrate are required
to react with 150. g of brass? [130. g Fe(NO3)3]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
____Zn
_____ Fe(NO3)3
____ Fe
_____ Zn(NO3)2
______________ 8. How many milliliters of sulfuric acid (density 1.80 g/mL) are required to
react with 7.43 g of aluminum? [answer: 22.5 mL sulfuric acid]
Item
ALUMINUM
+
SULFURIC
ACID
+
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
______________9. Steel wool is 25.0% iron by mass. If 525 g of steel wool reacts with an
excess of silver nitrate, how many grams of silver will be produced?
[answer: 761 g Ag]
Balanced
Equation
Question
Mole Ratio
Conversions
Needed
_____Fe
+
_____AgNO3
_____ Ag
+
_____ Fe(NO3)3