Question

$3$ moles of a gas requires $60cal$ heat for $5^{o}C$ rise of temperature at constant volume, then heat required for $5$ moles of same gas under constant pressure for ${10}^{o}C$ rise of temperature is $(R=2cal/mole-k)$

• A. $200cal$
• B. $400cal$
• C. $100cal$
• D. $300cal$

Answer 1

The correct option is D $300cal$

at const. volume

$\Delta Q=\Delta u=60cal$

$\Rightarrow \frac{f}{2}\times 3\times R\times \left(5\right)=60$

$\Rightarrow +=4$

${10}^{0}c$

Now at const pressure

for ${10}^{0}c$ rise

$\Delta Q=\frac{f}{2}\times 5\times R\times \left(10\right)+5\times R\times \left(10\right)$

$300$ cal$.$

Hence,

option $\left(D\right)$ is correct answer.