Дано

NxHy

w(H) = 17.65% = 0.1765

w(N) = 82.35% = 0.8235

Решение

w(N) = xAr(N) / (xAr(N) + yAr(H)) = 14x / (14x + y) = 0.8235

14x / (14x + y) = 0.8235

14x = 0.8235(14x + y)

14x = 11.529x + 0.8235y

2.471x = 0.8235y

3x = 1y

x : y = 1 : 3

NH3

Ответ: NH3