Question

MgNH4PO4•6H2O loses H2O in a stepwise fashion as it is heated. Between 40 degrees celsius and 60 degrees celsius, the monohydrate is formed. What is the percentage of phosphorus in the monohydrate? Enter your answer with 4 significant figures.

Answer 1

Answer:

$\%\ Composition\ of\ phosphorus=20.00\ \%$

Explanation:

The molecular formula of the monohydrate formed = $MgNH_4PO_4.H_2O$

The molecular mass of the monohydrate formed = $Mass_{Mg}+Mass_{N}+6\times Mass_{H}+5\times Mass_O$

So, Mass = 24 + 14 + 6 × 1 + 5 × 16 = 155 g

Mass of phosphorus = 31 g

Thus,

$\%\ Composition\ of\ phosphorus =\frac{Mass_{phosphorus}}{Total\ mass}\times 100$

$\%\ Composition\ of\ phosphorus=\frac{31}{155}\times 100$

$\%\ Composition\ of\ phosphorus=20.00\ \%$