a) What is the charge and mass of the anode rays emitted when, hydrogen gas is enclosed in the discharge tube experiment? What is the name of these particles?
b) Do the anode rays always consist of protons whatever be the gas enclosed in the discharge tube? Explain.

a) In the case of hydrogen gas the anode rays consist of protons. A proton possesses one unit of positive charge and one unit of mass.
b) No, only in the case of hydrogen gas the anode rays consists of protons. In all other cases the anode rays consist of positive ions whose mass and charge vary according to the nature of the gas enclosed.
The anode rays are obtained when valence electrons are removed in the form of cathode rays from the atoms of the enclosed gas on passing high voltage of current. Since hydrogen atom consists of one electron and one proton, removal of this electron is in the form of cathode rays, and only protons remain and tube protons appear in the form of anode rays.
But in other cases, for example oxygen, the anode rays consist of positive ions. Oxygen atom consists of two valence electrons which are removed in the form of cathode rays. The positive ion formed, carry two units of positive charge and mass 16(8p + 8n).