Question #97c8f

1 Answer
Sep 14, 2017

I think answer is 78 gm

Explanation:

% sum of all the elements = 100
% of H = 7.7
% left of remaining elements = 100-7.7 = 92.3%

now we find the % of other elements with help of ratio given

% of C = 3*92.3/9 = 30.77%
% of O = 2*92.3/9 = 20.51%
% of S = 4*92.3/9 = 41.02%

now to finding empirical formula, we divide % by the atomic masses of respective element

C 30.77/12 = 2.56
O 20.51/16 = 1.28
S 41.02/32 = 1.28
H 7.7/1 = 7.7
now we divide all these %-mass ratio by the smallest %-mass ratio i.e. 1.28

C 2.56/1.28 = 2
S 1.28/1.28 = 1
O 1.28/1.28 = 1
H 7.7/1.28 =approx. 6

so the empirical formula is C_2OSH_6 and mass is 24 + 16 + 32 + 6 = 78 gm