Calculate how many moles of productwould be produced if .310 mol of the first reactant were to react completely.
(a) CO2 + 4 H2 �¨ CH4 + 2 H2O
CH4 _____ mol
H2O _____ mol
(b) C3H8 + 5 O2 �¨ 4 H2O + 3 CO2
H2O _____ mol
CO2 _____ mol
(c) 3 H2SO4 + 2 Fe �¨ Fe2(SO4)3 + 3 H2Fe2(SO4)3 _____ mol
H2 _____ mol
(d) BaCl2 + 2 AgNO3 �¨ 2 AgCl+ Ba(NO3)2 AgCl _____ mol
Ba(NO3)2 _____ mol
To calculate the number of moles of a product produced when a certain amount of a reactant is consumed, we need to use the mole ratio from the balanced chemical equation.
(a) The balanced chemical equation for the reaction CO2 + 4 H2 → CH4 + 2 H2O tells us that for every 1 mole of CO2 that reacts, 1 mole of CH4 and 2 moles of H2O are produced. Since the mole ratio between CO2 and CH4 is 1:1, if 0.310 moles of CO2 react completely, then 0.310 moles of CH4 are also produced. Similarly, since the mole ratio between CO2 and H2O is 1:2, 0.310 moles of CO2 would produce 0.310 × 2 = 0.620 moles of H2O.
Therefore:
CH4: 0.310 mol
H2O: 0.620 mol
(b) The balanced chemical equation for the reaction C3H8 + 5 O2 → 4 H2O + 3 CO2 tells us that for every 1 mole of C3H8 that reacts, 4 moles of H2O and 3 moles of CO2 are produced. Since the mole ratio between C3H8 and H2O is 1:4, if 0.310 moles of C3H8 react completely, then 0.310 × 4 = 1.240 moles of H2O are produced. Similarly, since the mole ratio between C3H8 and CO2 is 1:3, 0.310 moles of C3H8 would produce 0.310 × 3 = 0.930 moles of CO2.
Therefore:
H2O: 1.240 mol
CO2: 0.930 mol
(c) The balanced chemical equation for the reaction 3 H2SO4 + 2 Fe → Fe2(SO4)3 + 3 H2 tells us that for every 3 moles of H2SO4 that reacts, 1 mole of Fe2(SO4)3 and 3 moles of H2 are produced. Since the mole ratio between H2SO4 and Fe2(SO4)3 is 3:1, if 0.310 moles of H2SO4 react completely, then 0.310/3 = 0.10333 moles of Fe2(SO4)3 are produced. Similarly, since the mole ratio between H2SO4 and H2 is 3:3 (or simply 1:1), 0.310 moles of H2SO4 would produce 0.310 moles of H2.
Therefore:
Fe2(SO4)3: 0.10333 mol
H2: 0.310 mol
(d) The balanced chemical equation for the reaction BaCl2 + 2 AgNO3 → 2 AgCl + Ba(NO3)2 tells us that for every 1 mole of BaCl2 that reacts, 2 moles of AgCl and 1 mole of Ba(NO3)2 are produced. Since the mole ratio between BaCl2 and AgCl is 1:2, if 0.310 moles of BaCl2 react completely, then 0.310 × 2 = 0.620 moles of AgCl are produced. Similarly, since the mole ratio between BaCl2 and Ba(NO3)2 is 1:1, 0.310 moles of BaCl2 would produce 0.310 moles of Ba(NO3)2.
Therefore:
AgCl: 0.620 mol
Ba(NO3)2: 0.310 mol