Volume of Carbon dioxide =11.2L

Temperature (T) = 273K

Pressure (P) =1 atm

Now we have to find no of moles of CO2 that is present in 11.2L,

PV= nRT

Where P = pressure,

V=volume,

N= no of moles,

R= gas constant, and

T=temperature

By putting values, we get

$$\Rightarrow 1\times 11.2=n\times 0.0821\times 273$$

$$\Rightarrow n=\frac{11.2}{22.4}=0.5mol$$

There are present 0.5moles of carbon dioxide in 11.2 liters at STP.

Since 1 mole of carbon dioxide contains 1 mole of carbon atoms and 2 mole of oxygen atoms.

So, 0.5 moles of carbon dioxide contains 0.5 moles of carbon atoms and 1 mole of oxygen atoms.

Therefore, the number of carbon atoms in 11.2 liters of carbon dioxide at STP

$$=0.5\times 6.023\times 10^{23}$$

$$= 3.0115\times 10^{23}$$

The number of oxygen atoms in 11.2 liters of carbon dioxide at STP

$$=1\times 6.023\times 10^{23}$$

$$= 6.023\times 10^{23}$$