Question

A sample of C3H8 has 8.08 × 1024 H atoms.

How many carbon atoms does the sample contain?

What is the total mass of the sample?

Answer 1

(8.08x10^24 H atoms)(3 C atoms/8 H atoms)
=3.03x10^24 C atoms
3.03x10^24+8.08x10^24=1.111x10^25 atoms total
(1.111x10^25)/(6.02x10^23)=18.4551495 mol C3H8
18.4551495(44.01)=812.2111296g C3H8

Answer 2

`3.03* 10^(24) atoms` of carbon in the sample.

73.7960 grams is the total mass of the sample.

Step-by-step explanation:

Compound =
`C_3H_8`

Total numbers of hydrogen atoms in a compound =
`8.08* 10^(24)` atoms

In one molecule of compound there are 8 hydrogen atoms.

Then x number of molecules of compound having
`8.08* 10^(24)` hydrogen atoms.

`x=(8.08* 10^(24))/(8) molecules=1.01* 10^(24) molecules`

In one molecule of compound there are 3 carbon atoms.

Then
`1.01* 10^(24) molecules` of given compound will have :

`3* 1.01* 10^(24) atoms=3.03* 10^(24) atoms` of carbon

`3.03* 10^(24) atoms` of carbon in the sample.

Moles of given compounds = n

`x=N_A* n`

`n=(N_A)/(x)=(1.01* 10^(24))/(6.022* 10^(23) mol^(-1))`

n = 1.6771 moles

Mass of 1.6771 moles of given compound:

`1.6771 mo* (3* 12 g/mol+8* 1 g/mol)=73.7960 g`

73.7960 grams is the total mass of the sample.