Question

A sample of K 3 P O 4 ( molar mass = 212.27 g/mol) contain s 1.5 24 ×10 24 potassium ions. What is the mass, in grams, of the potassium phosphate sample? ***Please Explain***

Answer 1

number of K+ = 1.524*10^24 ions

1 molecule of K3PO4 has 3 K+

So,

molecules of K3PO4 = number of K+ / 3

= 1.524*10^24)/3

= 5.08*10^23 molecules

we have below equation to be used:

number of mol = number of molecules / Avogadro’s number

number of mol = 5.08*10^23 / 6.022*10^23 mol

number of mol = 0.8436 mol

Molar mass of K3PO4 = 212.27 g/mol

we have below equation to be used:

mass of K3PO4,

m = number of mol * molar mass

= 0.8436 mol * 212.27 g/mol

= 1.791*10^2 g

Answer: 179.1 g