Topic 1.2: The mole concept

Question 1

Mole

Answer 1

Fixed amount, n, of a substance.

Question 2

Avogadro’s constant (NA)

Answer 2

6.02 x 1023 mol-1

Question 3

Isotopes

Answer 3

Atoms of the same element that have the same number of protons but different number of neutrons.

Question 4

Relative abundance

Answer 4

Measure of the percentage that occurs in a sample of the element.

Question 5

Relative atomic mass (AR)

Answer 5

Weighed average of the atomic masses of its isotopes and their relative abundances.

Question 6

Relative molecular mass

Answer 6

Sum of Ar values of the individual atoms or ions in one molecule.

Question 7

Formula of molar mass

Answer 7

n = m / Mr

Question 8

Qualitative analysis

Answer 8

Determining which elements are present in a compound.

Question 9

Quantitative analysis

Answer 9

Determining the relative masses of elements which allows them to work out their exact composition

Question 10

Empirical formula

Answer 10

Simplest whole number ratio of atoms or amount of each element present in a compound.

Question 11

Molecular formula

Answer 11

Actual number of atoms or amount of elements in one structural unit or one mole of the compound.