Question

1L of hydrocarbon at1270c and 1atm presure weighs 2.8g.It contains 10.5g of carbon per gram of hydrogen and its molecular formula will be​

Answer 1

Answer:

PV=nRT=

M

w

RT

or 1=

M

2.8

×0.0821×400

or M=91.95≈92

Let the formula be C

a

H

b

.

So 12a+b=92

b

12a

=10.5(given)

11.5b=92

or b=8

∴ a=7

Therefore, the formula is C

7

H

8

.

molar mass = 12*7+1*8 = 92gm/mole