Question

`You have to be careful about pouring drano down your pipes since it is mainly hydrochloric acid--you can't do it if they are made of aluminum because it will dissolve them! You can't acid clean your aluminum auto parts for the same reasons: 2 Al + 6 HCl → 2 AlCl3 + 3H2. If you were able to dissolve 10.0 mol of Al, how many many moles of hydrogen gas could you make? NOTE: All numbers located immediately after elemental symbols should be considered subscripts.
A. 3.00 moles
B. 6.00 moles
C. 1.50 moles
D. 15.0 moles
E. none of the above

Answer 1

Answer: The number of moles of hydrogen gas that will be produced is 15.0 moles.

Explanation:

We are given:

Moles of aluminum needed to be dissolved = 10.0 moles

For the given chemical reaction:

$2Al+6HCl\rightarrow 2AlCl_3+3H_2$

By Stoichiometry of the reaction:

2 moles of aluminium produces 3 moles of hydrogen gas

So, 10.0 moles of aluminium will produce = $\frac{3}{2}\times 10.0=15.0mol$ of hydrogen gas

Hence, the number of moles of hydrogen gas that will be produced is 15.0 moles.