Answer to Question #285691 in General Chemistry for Ahsan

Question

The molar heat capacity of a gas is given in the table below: T(K) 373 29.19 473 29.29 573 29.46 673 29.68 773 29.97 873 30.27 973 30.56 c_{D} (J/mol.K) a) Fit a 2 ^ (nd) order polynomial to the data to find c_{p} as a function of Temperature. Use the Cramer's Rule to solve the equations. Show all steps. b) Find the value of the heat capacity at 625 K using the equation derived in part a.

Answer 1

1) $\Delta E=nCvdT$

n=3

T₂=50^oC=323,15K

T₁=0^oC=273.15K

$\Delta E=nCvdT=3\times5\times(323.15-273.15)=750 cal$

2)

$\Delta H=nCpdT=n(Cv+R)dT$

$\Delta H=n(Cv+R)dT=3\times(5+2)\times(323.15-273.15)=1050 cal$