Question

How many grams of CaO are required to react with 852 g of $P_{4}O_{10}$?

• A. 852 g
• B. 1008 g
• C. 85 g
• D. 7095 g

Answer 1

Answer: (B)

1008 g

Answer 2

(2) : $6CaO + P_{4}O_{10} \rightarrow 2Ca_{3}(PO_{4})_{2}$

1 mole of $P_{4}O_{10} =$molar mass of $P_{4}O_{14} = 284g$

852 g of $P_{4}O_{10} = \frac{852}{284} = 3mol$

1 mole of $P_{4}O_{10}$reacts with 6 moles of $CaO$

3 moles of $P_{4}O_{10}$reacts with 18 moles of $CaO$

Mass of 18 moles of $CaO = 18 \times 56 = 1008g$