Stoichiometry!

Please note:
- Use 6.022x1023 for avogadro’s number
- Ignore sig figs and do not round the final answer.
- Keep it to 1 decimal place.

a) 13.2 moles

b) 79.33 grams of

Explanation:

First, we'll need to balance the equation

→

There are 2 (O) on the left and only one on the right, so we'll add a 2 coefficient to the right.

→

Now there are 4 (H) on the right and only 2 on the left, so we'll add a 2 coefficient to the () on the left.

→

The equation is now balanced.

a) This can be solved with a simple mole ratio.

4.6 moles × = 13.2 moles

b) This problem is solved the same way!

2.2 moles × = 2.2 moles

However, this problem wants the mass of , not the moles.

The molecular weight of is the weight of 4 (H) molecules and 2 (O) molecules (found on the periodic table). So,

4(1.008) + 2(15.999) = 36.03 g/mol

2.2 moles × = 79.33 grams of