Question

According to kinetic theory of gases the specific heat capacity of water (R = universal gas
constant)
(A) R
(B) 3R
(C) OR
(D) OR​

Answer 1

Answer:

Specific Heat Capacity of water

Consider water as solid,so it will have 'N' number of atoms.

1.Therefore for each atom average energy =3kBT.

2.No of molecules in H2O= 3 atoms.

3.Total internal energy U=3kBTx3xNA =9RT.

4.CV=CP=9R.

Answer 2

To find:

The specific heat capacity of water according to kinetic theory of gases

Calculation:

In order to calculate the specific heat celacity of water, water is considered as a solid.Water molecule has 2 hydrogen atoms and 1 oxygen atom

The internal energy of the molecule will be

   $U=3\times3k_BT\times N_A$

   $U=9K_BTN_A$

   $U=9(\frac{R}{N_A}) TN_A$

   $U=9RT$

In case of solids, the change in volume is approximately 0 when extremely high energy is supplied

  $\Delta Q= \Delta U+P \Delta V$

  $\Delta Q=\Delta U$

  $\Delta Q=9RT$

   $C=9R$

Final answer:

The specific heat capacity of water according to kinetic theory of gases is 9R