Respuesta :

Answer: Option C; K3N

Explanations:

1. Calculate number of moles for K and N

(i) Moles for K

mass = 89.3% = 89.3g

Mol. mass K =39.0983g/mol

∴ n = mass/molmass

=89.3/39.0988

=2.28 moles

(ii) Moles for N

mass = 10.7% = 10.7 g

Mol. mass N =14.0067g/mol

∴ n = mass/molmass

=10.7g/ 14.0067g/mol

=0.76 moles

2. Divide all components by the smallest value:

• K= 2.28 /0.76 = 2.9898240669737 ≈ 3

• N=0.76/0.76 = 1

Therefore emperical formula has 3 K and 1 N = K3N