Question

1. Mass number of an atom is the number of protons and?
2. The sub-atomic particle with a negligible mass?
3. An atom having stable electronics configuration ?
4. A molecule formed by sharing of electrons [covalency]?
5. A metallic atom having unstable electronic configuration?​

Answer 1

Answer:

1. neutron

2. electron

3. Helium (He)

4. covalent molecule

5. cadmium (Cd)