Question

How many hydrogen atoms are in 89.5 g of
C6H6 ?
Answer in units of atoms.

Answer 1

Molar mass of
`C_6H_6` is :

M = 6×12 + 6×1 g

M = 78 g

78 gram of
`C_6H_6` contains
`6.022 * 10^(23)` molecules.

So, 89.5 gram of
`C_6H_6` contains :

`n = 6.022 * 10^(23) * (89.5)/(78)\\\\n = 6.91 * 10^(23)`

Now, from the formula we can see that one molecule of
`C_6H_6` contains 2 hydrogen atom . So, number of hydrogen atom are :

`h = 2* 6.91 * 10^(23)\\\\h = 1.38 * 10^(22)\ atoms`

Hence, this is the required solution.