Question

Suatu senyawa nitrogen dan oksigen ternyata bersusun 30,0% nitrogen & 70,0% oksida. Bagaimana rumus molekul jika bobot molekulnya (90±2) sma ?
"cara nya juga ya, trimakasih "..

Answer 1

Mr = 92 sma

% N = 30%
% O = 70%

Asumsikan m = 100 gr

Maka
m N = 30 gr
m O = 70 gr

n N = m / Ar = 30 gr / 14 = 2,143 mol
n O = m / Ar = 70 gr / 16 = 4,375 mol

n N : n O = 2,143 : 4,375 = 1 : 2

Rumus empiris = NO2

Mr (NO2)x = x ( Ar N + 2 Ar O )
92 = x ( 14 + 2(16) )
92 = x ( 46 )
x = 2

Rumus molekul = N2O4