Question

How many atoms are in a `92.0*g` mass of ethyl alcohol?

Answer 1

Well, ethanol has a molar mass of `46.07*g*mol^-1`....and there are `6xxH+1xxO+2xxC="9 atoms per EtOH molecule"`

Explanation:

And thus we have a molar quantity of `(92*g)/(46.07*g*mol^-1)~=2.0*mol`

And it is a fact that one mole of stuff contains `6.022xx10^23` individual molecules....and so we have approx...

`2*molxx6.022xx10^23*mol^-1xx9*"atoms"`

`~=18*N_A` atoms, where `N_A-="Avocado number...."`

Answer 2

`~~2.0xx N_A" atoms " C_2H_5OH`

Explanation:

1. Ethanol is a simple alcohol also called ethyl alcohol with a chemical formula of `C_2H_5OH`. Its molar mass `(Mm)` is obtainable from the periodic table.

   `MmC_2H_5OH=(46.07g)/(mol)`

2. Given its mass, the mole relationship that 1mol of any substance is equivalent to `6.02xx10^23 (N_A)` number of atoms of that substance for the required molar conversionded ; i.e.,

   `1molC_2H_5OH-=6.02xx10^23 " atoms "C_2H_5OH`

3. Conversion processes are shown below.

From mass to mole:

`=92gcancel(C_2H_5OH)xx(1molC_2H_5OH)/(46.07cancel(gC_2H_5OH))`
`~~2.0molC_2H_5OH`

From mole to number of atoms:
`=2.0molC_2H_5OHxx(6.02xx10^23 " atoms " C_2H_5OH)/(1molC_2H_5OH)`
`=12.04xx10^23" atoms " C_2H_5OH`
`=1.2xx10^24" atoms " C_2H_5OH`