Question

How many moles of nitrogen gas are present in a 28.9 dm3 temperature of 55.0 °C and a pressure of 144 kPa?

Answer 1

Given :

Temperature, T = 55° C = ( 55 + 273 ) K = 328 K .

Volume of container, V = 28.9 dm³ = 0.0289 m³ .

Pressure, P = 144 kPa = 144000 Pa .

To Find :

Number of moles of nitrogen  gas.

Solution :

We know, by ideal gas equation :

PV = nRT  ( R ( universal gas constant ) = 8.31 J K⁻¹ mol⁻¹ .

$n = \dfrac{PV}{RT}\\\\n = \dfrac{144000\times 0.0289}{8.31 \times 328} \ moles\\\\n = \dfrac{4161.6}{2725.68}\\\\n = 1.53 \ moles$

Therefore, number of moles of nitrogen gas is 1.53 moles.