Explanation:
As per Brønsted-Lowry concept of acids and bases, chemical species which donate proton are called Brønsted-Lowry acids.
The chemical species which accept proton are called Brønsted-Lowry base.
(a) 
is Bronsted lowry acid and 
is its conjugate base.
is Bronsted lowry base and 
is its conjugate acid.
(b)
is Bronsted lowry base and HCN is its conjugate acid.
is Bronsted lowry acid and 
is its conjugate base.
(c)
is Bronsted lowry acid and 
is its conjugate base.
Cl^- is Bronsted lowry base and HCl is its conjugate acid.
(d)
is Bronsted lowry acid and 
is its conjugate base.
OH^- is Bronsted lowry base and is its conjugate acid.
(e)
is Bronsted lowry base and OH- is its conjugate acid.
is Bronsted lowry acid and OH- is its conjugate base.
Mass number is the number of protons and neutrons in an atom, and it tells us about the mass of the atom in amu, or atomic mass units. Atomic mass is the average mass of all the isotopes of a certain type. It is a weighted average that takes into account the abundances of all of the different isotopes
hope this helps :)
It tends to in increase because the size of the atoms increase.
Heating an atom excites its electrons and they jump to higher energy levels. When the electrons return to lower energy levels, they emit energy in the form of light. ... Every element has a different number of electrons and a different set of energy levels. Thus, each element emits its own set of colours.
