THE ATOM AND REDOX 2A

Question 1

Definition of atomic number

Answer 1

The number of protons in the nucleus of one atom of an element

Question 2

Definition of an isotope

Answer 2

An atom of the same element that has the same number of protons but different number of neutrons

Question 3

How to work out the mass number

Answer 3

The number of protons plus the number of neutrons

Question 4

Definition of relative isotopic mass

Answer 4

The mass of one atom of an isotope compared to 1/12 the mass of one atom of carbon-12

Question 5

Why is carbon-12 the standard

Answer 5

It can be obtained in an isotopically pure state and is unreactive

Question 6

Definition of relative atomic mass

Answer 6

The weighted average mass of one atom of an element compared to 1/12 the mass of one atom of carbon-12

Question 7

Definition of relative molecular mass (Mr)

Answer 7

The weighted mean mass of a molecule compared to 1/12 the mass of 1 atom of carbon-12

Question 8

Definition of relative formula mass (Mr)

Answer 8

The weighted mean mass of a formula unit compared to 1/12 the mass of 1 atom of carbon-12

Question 9

Definition of 1st ionisation energy

Answer 9

The amount of energy needed to remove 1 electron from each atom in 1 mole of gaseous atoms to form one mole of gaseous 1+ ions

Question 10

What are shielding electrons?

Answer 10

The electrons between the nucleus and other electron shells

Question 11

State and explain the general trend of first ionisation energy across period 2

Answer 11

The IE increases. The charge in the nucleus increases because the proton number increases and the number of shielding electrons stays the same therefore the overall electrostatic attraction is stronger so the IE is larger. The atomic radius is also slightly smaller.

Question 12

How many s orbitals are there?

Answer 12

1

Question 13

How many p orbitals are there?

Answer 13

3 - px, py, pz

Question 14

How many d orbitals are there?

Answer 14

5

Question 15

How many f orbitals are there?

Answer 15

7

Question 16

What is the term used for subshells that are of identical energy?

Answer 16

Degenerate

Question 17

Definition of oxidation

Answer 17

loss of electrons/gain of oxygen/loss of hydrogen

Question 18

Definition of reduction

Answer 18

gain of electrons

Question 19

Definition of oxidising agent

Answer 19

A reagent that oxidises another species and is reduced in the process

Question 20

Definition of reducing agent

Answer 20

A reagent that reduces another species and is oxidised in the process

Question 21

What is the term used to describe when the same substance is both reduced and oxidised?

Answer 21

Disproportionation

Question 22

Definition of orbital

Answer 22

Region of space that can hold up to 2 e- with opposite spin (and the same energy)

Question 23

Rules of oxidation number: Group 1 elements

Answer 23

Have an O.N of +1

Question 24

Rules of oxidation number: Group 2 elements

Answer 24

Have an O.N of +2

Question 25

Rules of oxidation number: Fluorine atoms

Answer 25

Have an O.N of -1

Question 26

Rules of oxidation number: Oxygen atoms

Answer 26

Have an O.N of -2 except when in a peroxide

Question 27

Rules of oxidation number: Hydrogen atoms

Answer 27

Have an O.N of +1 except when in a hydride

Question 28

Definition of molar mass

Answer 28

The mass per mole of a substance. The units of molar mass are g mol⁻¹