# How many formula units of aluminum are required to produce 9.9 grams of hydrogen in 2Al + 3H_2SO_4 -> Al_2(SO_4)_3 + 3H_2?

May 16, 2016

You have the balanced chemical equation. $\text{Moles of dihydrogen = "3/2xx"moles of aluminum}$

#### Explanation:

Given the stoichiometric equation, you have established the stoichiometry.

$\text{Moles of dihydrogen}$ $=$ $\frac{9.9 \cdot g}{2.0 \cdot g \cdot m o {l}^{-} 1}$ $=$ ??*mol.

The moles of aluminum metal is $\frac{2}{3}$ this quantity.

And of course $\text{1 mole}$ $=$ $6.022 \times {10}^{23} \text{ formula units}$.