Question

examples of pseudo scalar

Answer 1

A pseudoscalar is a quantity in physics that behaves like a scalar, except for the fact that it changes sign under a parity inversion like improper rotations, but a true scalar does not change sign.

Example pseudoscalars:

By math, Magnetic charge is a pseudoscalar, despite the fact that it exists physically or not.

Helicity is the projection of a spin pseudovector onto the direction of momentum.

Pseudoscalar particles is the one  with spin 0 and odd parity, or otherwise referred to a particle with no intrinsic spin with wave function that changes sign under parity inversion.

Another example is pseudoscalar mesons