Question

X and H form two compounds. They contain 17.65% and 12.50% hydrogen by mass respectively. If the first compound is XH3 then second one could be options: 1)X2H4 2)XH 3)X2H 4)X3H?​

Answer 1

$\huge\mathfrak\pink{Answer}$

$\sf\pink{The \ Correct \ option \ is \ 3.}$

$<p style="color:black;font-family:cursive;background:black,;font-size25px;">$ Let m.....be atomic mass of ..Xin first compound....XH3%by mass of hydrogen = mass of hydrogen/ molar mass=>17.65/100 = 3 /(m+3) =>17.65×(3+m) = 300 =>17.65m = 300 - 17.65×3 = 300 - 52.95 =>17.65m = 247.05 => m = 247.05/17.65 ≈ 14gin second compound ......XH(y).... %by mass of hydrogen = mass of hydrogen/ molar mass=> 12.5/100 = y/(14+y)=> 12.5×(14+y) = 100y=> 12.5×14 = (100-12.5)y=> y = 175/87.5= 2it means .....second compound is....XH2....but as in option... it is not given......The answer would be......X2H4 [ as X2H4 and XH2 ...have ...X. & H in same ratio....which is ...{1:2}.....]