2.1.1 Atomic Structure and Isotopes , 2.1.2 Compounds, Formulae and Equations, 2.1.3 Amount of Substance

Question 1

Relative Atomic Mass Definition

Answer 1

The weighted mean mass of an atom of an element compared with one twelfth of the atom of carbon-12 ( This is the weighted mean of all the isotopic mass taking into account their abundance

Question 2

Relative Molecular Mass Definition

Answer 2

The weighted mean mass of a molecule compared with one twelfth of the mass of an atom of carbon- 12

Question 3

Relative Mass Definition

Answer 3

The weighted mean mass of a formula unit of a substance compared with one-twelfth of the mass of an atom of carbon-12 (This is useful for substances such as sodium chloride (an ionic lattice), which do not contain molecules.)

Question 4

Relative Isotopic Mass Definition

Answer 4

The mass of one atom of an isotope, compared with one-twelfth of the mass of an atom of carbon-12 (For a single isotope e.g. 37Cl or 35Cl)

Question 5

Isotope Defintion

Answer 5

Atoms of an element with the same number of protons and a different number of neutrons

Question 6

Recall the ions charge, name and formula NO(3), CO(3), SO(4), OH, NH(4), Zn, Ag

Answer 6

NO(3)- > Nitrate
CO(3)2- > Carbonate
SO(4)2- > Sulphate
OH- >Hydroxide
NH(3)+ > Ammonia
Zn2+ > Zinc
Ag+ > Silver

Question 7

Hydrated Definition

Answer 7

Crystalline formed contains water

Question 8

Anhydrous Defintion

Answer 8

Crystalline formed doesn’t contain water

Question 9

Empirical Formula Defintion

Answer 9

Simplest whole number ratio of atoms of each element in a compound

Question 10

Molecular Formula Defintion

Answer 10

Number and type of atoms of each element in a molecule

Question 11

Orbital Defintion

Answer 11

The area around the nucleus which can hold up to two electrons with opposite spin

Question 12

Weighted mean mass definition

Answer 12

The average mass taking into account the relative abundancies of the isotope