The molar specific heat of oxygen at constant pressure Cp=7.03 cal / mol ° C and R =8.31 J / mol ° C. The amount of heat taken by 5 moles of oxygen when heated at constant volume from 10° C to 20° C will be approximately.

Question

The molar specific heat of oxygen at constant pressure Cp=7.03 cal / mol ° C and R =8.31 J / mol ° C. The amount of heat taken by 5 moles of oxygen when heated at constant volume from 10° C to 20° C will be approximately. (A) 25 cal (B) 50 cal (C) 253 cal (D) 500 cal

Tardigrade Admin · Accepted Answer

Given, Cp=7.03 cal / mol ° C , R =8.315 / mol ° C, n =5 moles, T2=20° C , T1=10° C, Δ Q =? ∴ Heat, Δ Q =n CV Δ T=n(Cp-R) Δ T =5[7.03-(831/4.2)] ×(20-10) ≃ 253 cal

Q. The molar specific heat of oxygen at constant pressure $C_{p} = 7.03 c a l / m o l^{\circ} C$ and $R = 8.31 J / m o l^{\circ} C$ . The amount of heat taken by $5$ moles of oxygen when heated at constant volume from $1 0^{\circ} C$ to $2 0^{\circ} C$ will be approximately.

25 cal

50 cal

253 cal

500 cal

Given, $C_{p} = 7.03 c a l / m o l^{\circ} C, R = 8.315/ m o l^{\circ} C$ ,
$n = 5$ moles, $T_{2} = 2 0^{\circ} C, T_{1} = 1 0^{\circ} C$ ,
$Δ Q = ?$
$∴$ Heat, $Δ Q = n C_{V} Δ T = n (C_{p} - R) Δ T$
$= 5 [7.03 - \frac{831}{4.2}] \times (20 - 10) ≃ 253 c a l$

Q. The molar specific heat of oxygen at constant pressure Cp​=7.03cal/mol∘C and R=8.31J/mol∘C. The amount of heat taken by 5 moles of oxygen when heated at constant volume from 10∘C to 20∘C will be approximately.