Question

What is the percent composition by mass for sodium (Na) in sodium phosphate (Na3PO4)? % Na = (______/______)x100% = _______% NNA​

Answer 1

The percent composition by mass for sodium (Na) in Sodium phosphate (Na₃PO₄) : 42.07%

Further explanation

Given

Compound of Sodium phosphate (Na₃PO₄)

Required

The percent composition by mass for sodium (Na)

Solution

The Comparative Law (Proust ) : compounds are formed from elements with the same Mass Comparison

MW Na₃PO₄ = 163,94 g/mol

Ar Na=22,989769g/mol

$\tt \%mass~Na=\dfrac{3.Ar~Na}{MW~Na_3PO_4}\times 100\%\\\\\%mass~Na=\dfrac{3\times 22.99}{163.94}\times 100\%\\\\\%mass~Na=42.07\%~Na$