# 7.5.2: Practice Stoichiometry part 1

#### Mole to Mole Conversions

Exercise $$\PageIndex{1}$$

Fe2O3 (s) + 3 CO (g) $$\rightarrow$$ 2 Fe (s) + 3 CO2 (g)

For the reaction above, how many moles of Fe would be produced from 0.877 moles Fe2O3?.

1.75 mol Fe

How many moles of CO2 would be produced from 0.438 moles Fe2O3?.

1.31 mol CO2

How many moles of Fe would be produced from 0.545 moles CO?.

0.363 mol Fe

#### Mass to Mass Conversions

Exercise $$\PageIndex{1}$$

Mg3N2 (s) + 6 H2(l) $$\rightarrow$$ 3 Mg(OH)2 (s) + 2 NH3 (g)

How many grams of H2O would react with 34.88 grams Mg3N2?

$$34.88 g Mg_3N_2 \times \dfrac{1 mol Mg_3N_2}{100.95 g Mg_3N_2} \times \dfrac{6 mol H_2O}{1 mol Mg_3N_2} \times \dfrac{18.02 g H_2O}{1 mol H_2O}$$

= 37.36 g H2O

How many grams of NH3 would be produced from 76.77 grams Mg3N2?.

$$76.77 g Mg_3N_2 \times \dfrac{1 mol Mg_3N_2}{100.95 g Mg_3N_2} \times \dfrac{2 mol NH_3}{1 mol Mg_3N_2} \times \dfrac{17.04 g NH_3}{1 mol NH_3}$$

= 25.92 g NH3

How many grams of Mg(OH)2 are produced from 46.32 g H2O?

$$46.32 g H_2O \times \dfrac{1 mol H_2O}{18.02 g H_2O} \times \dfrac{3 mol Mg(OH)_2}{6 mol H_2O} \times \dfrac{58.33 g Mg(OH)_2}{1 mol Mg(OH)_2}$$

= 74.97 g Mg(OH)2

#### Mixed Stoichiometry

Exercise $$\PageIndex{1}$$

C3H8 (g) + 5 O2 (g) $$\rightarrow$$ 3 CO2 (g) + 4 H2O (g)

How many grams of O2 are needed to produce 4.22 moles of CO2?

225 grams of O2

How many moles of C3H8 produce 87.8 grams of H2O?