Question

Empirical formula of a compound is C2H5O and it's molecular weight is 90 .molecular formula of the compound is
A. C2H5O
B. C3H6O3
C. C4H10O2
D. C5H14O2

Answer 1

Answer:

option 'c' is correct.

Explanation:

emprical formula=>C2H5O

mass=>90u

therefore,molecular formula is given by,

C2xH5xOx (x is no. of atoms.)

since Mass of 2carbon is 12u*2=24u

therefore,

mass of x carbon atom=24x u.

Similarly,

mass of x hydrogen atom=5x u

and

mass of x oxygen atom=16x u

now,

atq

24x+5x+16x=90

45x=90

x=2

putting x in formula we get....

C4H10O2