Draw a neat labeled diagram representing an atom. Name the three sub-atomic particles in the atom & represent them symbolically showing the mass & charge of each. State where the sub-atomic particles are present in the atom.

Define the term - 'atomic number' of an atom. If an atom 'A' has an atomic number of - eleven, state the number of protons & electrons it contains.

State why the atomic weight of an element is also termed - relative atomic mass.

State how electrons are distributed in an atom. Explain in brief the rules which govern their distribution.