Question

When 100 J of heat is given to an ideal gas it expands from 200 $c{m}^3$ to 400 $c{m}^3$ at a constant pressure of $3\times {10}^5$ Pa. Then calculate the number of moles in the gas if the initial temperature is 400 K ,$R=[8.314J/mol-k]$

• A. $\frac{9}{500}moles$
• B. $\frac{7}{500}moles$
• C. $\frac{3}{500}moles$
• D. None of these

Answer 1

Answer: (A)

$\frac{9}{500}moles$

Using the ideal gas law,
PV = nRT
Thus, n = $\frac{PV}{RT}$
Substituting, the initial values of the quantities given,
n = $\frac{9}{500}$