When a fixed amount of ideal gas goes through an isochoric process:

its temperature must increase.
its pressure must increase.
its internal (thermal) energy does not change.
no heat enters or leaves the gas.
the gas does no work.

the gas does no work.

Explanation:

An isochoric process is a process in which the volume of a gas is kept constant.

The work done by a gas during a transformation is given by:

where

p is the gas pressure

is the change in volume of the gas

For an isochoric process, the volume of the gas does not change, so

and so, according to the previous equation, the work done by the gas is zero:

W = 0