10g of oxygen was introduced in an evacuated container of 5 dm3 volume at 27 C calculate pressure of gas in Nm-2

^{3}

Temperature (T) = 27 + 273 = 300 K

Mass of oxygen gas = 10 g

Number of moles (n) = $\frac{\text{Givenmass}}{\text{Molarmass}}$ = $\frac{10}{32}$

n = 0.3125 moles

Value of gas constant (R) = 8.314 kPa dm

^{3}K

^{-1}mol

^{-1}

Now , applying the formula ,

PV = nRT

P = $\frac{\text{nRT}}{\text{V}}$

Putting the values in the formula ,

P = $\frac{0.3125\times 8.314\times 300}{5}$

P = 155.88 kPa

1 kPa = 1000 Nm

^{-2}

155.88 kPa = 155.88$\times $ 1000 = 155880 Nm

^{-2}

**
**