What is the mass and size of a white dwarf?
A White dwarf is the left over core from the death of a normal sized Star like our Sun. A white dwarf has typically the mass of the Sun but is about the same size as the Earth so small and extremely massive.
Take an example of Sirius B. Sirius B is a White dwarf at about 10 light-years from the Sun. Its about the same mass as the Sun about 2 Solar Masses (2 x