# 6.E: Quantities in Chemical Reactions (Exercise)

1. If the average male has a body mass of 70 kg, of which 60% is water, how many moles of water are in an average male?

2. If the average female is 60.0 kg and contains 0.00174% iron, how many moles of iron are in an average female?

3. How many moles of each element are present in 2.67 mol of each compound?

1. HCl
2. H2SO4
3. Al(NO3)3
4. Ga2(SO4)3
4. How many moles of each element are present in 0.00445 mol of each compound?

1. HCl
2. H2SO4
3. Al2(CO3)3
4. Ga2(SO4)3
5. What is the mass of one hydrogen atom in grams? What is the mass of one oxygen atom in grams? Do these masses have a 1:16 ratio, as expected?

6. What is the mass of one sodium atom in grams?

7. If 6.63 × 10−6 mol of a compound has a mass of 2.151 mg, what is the molar mass of the compound?

8. Hemoglobin (molar mass is approximately 64,000 g/mol) is the major component of red blood cells that transports oxygen and carbon dioxide in the body. How many moles are in 0.034 g of hemoglobin?

1. 2,330 mol

2. 0.0187 mol
1.

1. 2.67 mol of H and 2.67 mol of Cl
2. 5.34 mol of H, 2.67 mol of S, and 10.68 mol of O
3. 2.67 mol of Al, 8.01 mol of N, and 24.03 mol of O
4. 5.34 mol of Ga, 8.01 mol of S, and 32.04 mol of O
4.
1. 0.00445 mol of H and 0.00445 mol of Cl
2. 0.00890 mol of H, 0.00445 mol of S, and 0.0178 mol of O
3. 0.00890 mol of Al, 0.0134 mol of C, and 0.0401 mol of O
4. 0.00890 mol of Ga, 0.0134 mol of S, and 0.0534 mol of O
5. H = 1.66 × 10−24 g and O = 2.66 × 10−23 g; yes, they are in a 1:16 ratio.

6. 3.816 x 10-23 g

7. 324 g/mol

8. 5.3 x 10-7 mol