Question

Can someone help me with Q4 MCQ? I would like to have an explanation pls. Thanks, will mark brainliest.

Answer 1

Answer:

B

Explanation:

The ratios of the coefficient of the compounds in a balanced chemical equation tells us the relationship of each compound to the others in terms of mole.

Based on the equation,

3 moles of CO₂ would require 2 moles of phosphoric acid.

3 mol CO₂ ------- 2 mol H₃PO₄

1.5 mol CO₂ ------- 2 ÷2= 1 mol H₃PO₄

Or 1.5 mol would require $\frac{1.5}{3} \times 2$ mol of  H₃PO₄

To find mass of  H₃PO₄, multiply the number of moles by its Mr, which can be deduced with the help of the periodic table.

Ar of  H₃PO₄

= 3(Ar of H) + Ar of P +4(Ar of O)

= 3(1) +31 +4(16)

= 98

Multiply 98 with the number of moles, 1, to obtain the answer.

So if you would look at the steps above, here's what we did:

$\frac{1.5 \times 2}{3} \times 98 \\ = \frac{1.5 \times 2 \times 98}{3}$