\( 2.2 g \) of nitrous oxide \( \left( N _{2} O \right) \) gas is cooled at a constant pressure of \( 1 atm \) from \( 310 K \) to \( 270 K \) causing the compression of the gas from \( 217.1 mL \) to \( 167.75 mL \). The change in internal energy of the process, \( \Delta U \) is ' \( - x \) ' J. The value of ' \( x \) ' is _. [nearest integer] (Given: atomic mass of \( N =14 g mol ^{-1} \) and of \( O =16 g mol ^{-1} \). Molar heat capacity of \( N _{2} O \) is \( 100 JK ^{-1} mol ^{-1} \) ).

Question

\( 2.2 g \) of nitrous oxide \( \left( N _{2} O \right) \) gas is cooled at a constant pressure of \( 1 atm \) from \( 310 K \) to \( 270 K \) causing the compression of the gas from \( 217.1 mL \) to \( 167.75 mL \). The change in internal energy of the process, \( \Delta U \) is ' \( - x \) ' J. The value of ' \( x \) ' is _. [nearest integer] (Given: atomic mass of \( N =14 g mol ^{-1} \) and of \( O =16 g mol ^{-1} \). Molar heat capacity of \( N _{2} O \) is \( 100 JK ^{-1} mol ^{-1} \) ).

Answer 1

\(\Delta T=-40K\)

\(\Delta U =q+w\)

\(=\frac{100\times 2.2}{44}(-40)-(-49.39)\times10^{-3}\times 101.325\)

\(=-200+5\)

= - 195 J

X= 195