Science puzzle

2. the number of protons in the nucleus of an atom is called the atomic number
5. any elements in the group VIIA (17) of the periodic table are called halogens
6. a covalent bond is a chemical bond that involves the sharing of electron pairs between atoms
12. an abbreviation for an element on the periodic table is called a symbol
13. any elements in Group IA (1) of the periodic table are called alkali or alkali metals
16. a solution is a special type of homogeneous mixture composed of two or more substances
18. the rapid vaporization of a liquid is boiling called
20. phase transition from the liquid phase to vapor is called vaporization

1. the transition of a substance directly from the solid to the gas state is called sublimation
3. Ions are atoms or molecule that has a net electrical charge
4. the state or power of being reactive or the degree to which a thing is reactive is called reactivity
7. the quality of being toxic or poisonous is called toxicity
8. the smallest component of an element is an atom
9. A solid becoming liquefied by heat is melting called
10. the ease with which a combustible substance can be ignited is called flammability
11. elements in group 2 of the periodic table are called alkaline or alkaline metals
14. a thing composed of two or more separate elements is called a compound
15. the mass of an atom is called the atomic mass
17. the level of acid in substances is called acidity
19. chemical bonding that involves the electrostatic attraction between oppositely charged ions is called IONIC bonding