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An unknown compound containing carbon and hydrogen analyzes to be 92.26% C. A 0.293 g sample of the gas occupies 185 mL at 374 mm Hg and 23.0°C. What is the molecular formula?

User Alkhader
by
3.2k points

1 Answer

7 votes

Answer:The empirical formula is

C

4

H

11

O

2

.

Step-by-step explanation:First, we calculate the masses of

C

and

H

from the masses of their oxides (

CO

2

and

H

2

O

).

Mass of C

=

1.900

g CO

2

×

12.01 g C

44.01

g CO

2

=

0.5185 g C

Mass of H

=

1.070

g H

2

O

×

2.016 g H

18.02

g H

2

O

=

0.1197 g H

Mass of C + Mass of H

=

0.5185 g + 0.1197 g

=

0.6382 g

This is less than the mass of the sample.

The missing mass must be caused by

O

.

Mass of O = 0.9827 g - 0.6382 g = 0.3445 g

User Radmen
by
3.0k points