Question

A triatomic molecule in the shape of triangle can be assumed that atoms or at vertices of a triangle and joined by mass less rods. Internal energy of one mole at temperature T is​

Answer 1

A triatomic molecule in the shape of triangle can be assumed that atoms at vertices of the triangle and joined by massless rods.

To find : internal energy of one mole at temperature T is ......

solution : first find degree of freedom of triatomic molecule.

degree of freedom is given by, f = 3N - n

where N is no of atoms , n is holonomic constraints.

here there three atoms and the seperation between three atoms are fixed so holonomic constraints is 3.

now, f = 3 × 3 - 3 = 6

now internal energy, U = f/2 RT

= 6/2 RT

= 3RT

Therefore the internal energy of one mole at temperature T is 3RT.