PROBLEM 30P

Consider the unbalanced equation for the reaction of aluminum with sulfuric acid:

Al(s) + H2SO4(aq) → Al2(SO4)3(aq) + H2(g)

(a) Balance the equation.

(b) How many moles of H2SO4 are required to completely react with 8.3 mol of Al?

(c) How many moles of H2 are formed by the complete reaction of 0.341 mol of Al?

Solution 30P

Step 1:

(a)The above chemical equation can be balance as follows

Al(s) + H2SO4(aq) → Al2(SO4)3(aq) + H2(g)

Number of Al atom in the reactant is one, where as in product is two, in order to balance the total number of Al atoms, multiply 2 with Al.

2Al(s) + H2SO4(aq) → Al2(SO4)3(aq) + H2(g)

Now, to balance total number of SO4 , in both reactant and product, multiply 3 with H2SO4(aq) and the number of H atoms can be balance by multiplying 3 with H2.

2Al(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 3H2(g)