Answer
a. $ 6.00 \space moles \space H$
b. $ 8.00 \space moles \space O$
c. $1.20 \times 10^{24} \space P \space atoms$
d. $ 4.80 \times 10^{24} \space P \space atoms$
Work Step by Step
a. Each $H_3PO_4$ has 3 $H$ atoms. Thus: $1 \space mole \space H_3PO_4 = 3 \space moles \space H$
$$2.00 \space moles \space H_3PO_4 \times \frac{3 \space moles \space H}{1 \space moles \space H_3PO_4} = 6.00 \space moles \space H$$
b. Each $H_3PO_4$ has 4 $O$ atoms. Thus: $1 \space mole \space H_3PO_4 = 4 \space moles \space O$
$$2.00 \space moles \space H_3PO_4 \times \frac{4 \space moles \space O}{1 \space moles \space H_3PO_4} = 8.00 \space moles \space O$$
- In 2.00 moles of $H_3PO_4$ we have:
$$2.00 \space moles \times \frac{6.02 \times 10^{23} \space molecules}{1 \space mole} = 1.20 \times 10^{24} \space molecules$$
c. Each $H_3PO_4$ has 1 $P$ atom.
$$1.20 \times 10^{24} \space H_3PO_4 \space molecules \times \frac{1 \space P \space atom}{1 \space H_3PO_4 \space molecules} = 1.20 \times 10^{24} \space P \space atoms$$
d. Each $H_3PO_4$ has 4 $O$ atoms.
$$1.20 \times 10^{24} \space H_3PO_4 \space molecules \times \frac{4 \space O \space atoms}{1 \space H_3PO_4 \space molecules} = 4.80 \times 10^{24} \space P \space atoms$$
