Download PRACTICE – Naming and Writing Ionic Compounds

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PRACTICE – Stoichiometry
1. Chlorine is used by textile manufacturers to bleach cloth. Excess chlorine is
destroyed by its reaction with sodium thiosulfate, Na2S2O3:
Na2S2O3(aq) + 4Cl2(g) + 5H2O(aq)  2NaHSO4(aq) + 8HCl(aq)
a. How many moles of Na2S2O3 are needed to react with 0.12mol of Cl2?
b. How many moles of HCl can form from 0.12mol of Cl2?
c. How many moles of H2O are required for the reaction of 0.12mol of Cl2?
d. How many moles of H2O react if 0.24mol HCl is formed?
2. The incandescent white of a fireworks display is caused by the reaction of
phosphorus with oxygen to give tetraphosphorus decoxide.
a. Write the balanced chemical equation for the reaction.
b. How many grams of O2 are needed to combine with 68.5g of phosphorus?
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c. How many grams of P4O10 can be made from 8.00g of O2?
d. How many grams of phosphorus are needed to make 7.46g of P4O10?
3. In dilute nitric acid, HNO3, copper metal dissolves according to the following
equation:
3Cu(s) + 8HNO3(aq)  3Cu(NO3)2(aq) + 2NO(g) + 4H2O(aq)
How many grams of HNO3 are needed to dissolve 11.45g of Cu?
4. In the reaction:
KClO3 + 5KCl + 6HNO3 --> 6KNO3 + 3Cl2 + 3H2O
how many grams of KClO3 are required to prepare 10.0 g of Cl2?
5. How many grams of HCl are required to react completely with 1.00 g of Zn to form
ZnCl2 and H2?
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6. If 12.0 g CH4 and 24.0 g O2 react to form CO2 and H2O, how many grams of CO2 will
be formed?
7. Methane (CH4) reacts with O2 to form CO2 and water. If 30.0 grams of CH4 and 64.0
grams of O2 are mixed and the reaction goes to completion, how many grams of H2O
will form?
8.
LiOH + HBr  LiBr + H2O
If you start with ten grams of lithium hydroxide, how many grams of lithium
bromide will be produced?
9.
C2H4 + 3 O2  2 CO2 + 2 H2O
If you start with 45 grams of ethylene (C2H4), how many grams of carbon dioxide will
be produced?
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Mg + 2 NaF  MgF2 + 2 Na
If you start with 5.5 grams of lithium chloride, how many grams of calcium chloride
will be produced?
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