Answer
The mass of propane that will produce 7.25 moles of water is equal to:
$ 79.9g$
Work Step by Step
- Balance the reaction:
$C_3H_8 + O_2 -- \gt CO_2 + H_2O$
- Balance the $C$:
$C_3H_8 + O_2 -- \gt 3CO_2 + H_2O$
- Balance the $H$:
$C_3H_8 + O_2 -- \gt 3CO_2 + 4H_2O$
- Balance the $O$:
Products: 3*2 + 4*1 = 10 oxygens:
$C_3H_8 + 5O_2 -- \gt 3CO_2 + 4H_2O$
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1. Calculate the molar mass of propane: $C_3H_8$:
12.01* 3 + 1.008* 8 = 44.09g/mol
2. Use the coefficients and the molar mass as conversion factors.
$7.25 mol(H_2O) \times \frac{1mol(C_3H_8)}{4mol(H_2O)} \times \frac{44.09g(C_3H_8)}{1mol(C_3H_8)} = 79.9g(C_3H_8)$
