Chemistry

3. process that involves addition(gain) of electrons
4. the smallest form of a chemical particle that retains the properties of the particle
5. chemical _______ may be defined as an attraction between the two atoms in a molecule
7. the central part of an atom consists of protons and neutrons
8. type of bond is formed by the mutual sharing of pair of electrons between two atoms each atom supplying equal number of electrons for sharing
9. elements belongs to groups 1A to 7A
12. unit of measurement used in chemistry to
14. amounts of a chemical substance
16. ______metals are elements that belong to 1B to 8B
18. positively charged particle
19. type of bond is formed as a result of the complete transfer of one or more electrons from one atom to other

1. electrons present in the outer most orbit
2. _____ number is the number protons present in the nucleus of an atom or number of electrons revolving around the nucleus in an atom
6. atoms of the same elements having the same atomic number but different mass number
8. branch of science that deals with the study of the nature of matter, its composition, occurrence, isolation, methods of preparation, properties and uses.
10. process that involves removal(loss) of electron
11. a negatively charged particle.
12. _______ number of an element is given by the total number of protons and neutrons present in the nucleus of an atom.
13. neutral particle
15. Electron ____ notation represents the distribution of valence electrons of an element
17. atoms of different elements having the same mass number but different atomic number.