Question

A compound with an empirical formula of CFBrO and a molar mass of 254.7 grams per mole.

Answer 1

Answer:

Molar mass of compound (

381.01

g

/

m

o

l

) has been provided for you.

Now you need to calculate the molar mass of

C

F

B

r

O

.

The molar mass of:

C

=

12.0

g

/

m

o

l

F

=

19.0

g

/

m

o

l

B

r

=

79.9

g

/

m

o

l

O

=

16.0

g

/

m

o

l

The molar mass of empirical formula, therefore (

C

F

B

r

O

) is:

12.0

+

19.0

+

79.9

+

16.0

=

126.9

g

/

m

o

l

.

In order to get the molecular formula of

C

F

B

r

O

,

divide molar mass of compound by molar mass of empirical formula, like this:

molar mass of compound

molar mass of empirical formula

=

whole number

i.e.

381.01

126.9

=

3.00

Rounded to nearest whole number

Now, multiply the whole number by the Empirical Formula.

Like this

(

C

F

B

r

O

)

×

3

=

C

3

F

3

B

r

3

O

3

.

Therefore your molecular formula is

C

3

F

3

B

r

3

O

3

.