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Mole, Empirical and Stoichiometry Calculations

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Mole Calculations (Determining Avogadro's Number):
1. Calculate the mass of carbon in a diamond that contains 3.33 x 1024 atoms of C.
2. Calculate the mass of chloroform that contains 1,000,000,000,000 molecules of CHCL3.
3. Calculate the number of NaCL formula units in 1.37 g of table salt.
4. Calculate the number of N2 molecules in 0.111 g of nitrogen gas.

Empirical Formula Calculations (Compounds):
5. A 0.750 g sample of tin metal reacts with o.201 g of oxygen gas to form tin oxide.Calculate the empirical formula of tin Oxide.
6. A 0.565 g sample of cobalt metal reacts with excess sulfur to give 1.027 g of cobalt sulfide. Calculate the empirical formula of the product.
7. A 1.164-g sample of iron filings reacts with chlorine gas to give 3.384 g of iron chloride. Calculate the empirical formula of the product?
8. A 0.626 g sample of copper oxide was reduced to 0.500 g of copper metal by heating in a stream of hydrogen gas. Calculate the empirical formula of the copper oxide.

Stoichiometry Calculations (Precipitating Calcium Phosphate) :
9. A 0.914-g sample of stannous fluoride gives a 1.078-g precipitate of stannous phosphate. Calculate the theoretical yield and percent yield of Sn3(Po4)2.
10. A 10.000-g sample of toothpaste containing stannous fluoride gives a 0.145-g precipitate of stannous phosphate. What is the percentage of SnF2 in the toothpaste sample?

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Stoichiometry Problems, Limiting Reagent, Acid/Base, Balancing Chemical Equations

1. A solution is prepared by dissolving 10.8g ammonium sulfate in enough water to make 100.0mL of stock solution. A 10.00mL sample of this stock solution is added to 50.00mL of water. Calculate the concentration of ammonium ions and sulfate ions in the final solution.

2. One of the most commonly used white pigments in paint is a compound of titanium and oxygen that contains 59.9% Ti by mass. Determine the empirical formula of this compound.

3. A compound that contains only nitrogen and oxygen is 30.4% N by mass; the molar mass of the compound is 92g/mol. What is the empirical formula of the compound? What is the molecular formula of the compound?

4. Mercury and bromide will react with each other to produce mercury (II) bromide:
Hg(l) + Br2(l)  HgBr2(s)
a) What mass of HgBr2 can be produced form the reaction of 10.0g Hg and 9.00g Br2? What mass of which reagent is left unreacted?
b) What mass of HgBr2 can be produced form the reaction of 5.00mL mercury (density = 13.6g/mL) and 4.00mL bromine (density = 3.10g/mL)?

5. Consider the following unbalanced reaction:
Ca3(PO4)2 + H2SO4  CaSO4 + H3PO4
What masses of calcium sulfate and phosphoric acid can be produced from the reaction of 1.0kg calcium phosphate with 1.0kg concentrated sulfuric acid (98% H2SO4 by mass)?

6. What volume of each of the following acids will react completely with 50.00mL of 0.200M NaOH?
a) 0.100 M HCl
b) 0.150 M HNO3
c) 0.200 M HC2H3O2 (1 acidic hydrogen)

Thanks in advance! See attached for full problem.

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