Module 3 - Periodic Table and Energy

Question 1

Atomic (Proton) Number

Answer 1

The number of protons in the nucleus of an atom.

Question 2

Bohr Model

Answer 2

Describes an atom as a small dense nucleus with electrons orbiting around the nucleus. This model explains different periodic properties of atoms.

Question 3

Cations

Answer 3

Positively charged ions.

Question 4

d-block

Answer 4

The part of the periodic table in which the elements have their highest energy electron in a d-orbital.

Question 5

Electron Configuration

Answer 5

The arrangement of electrons into orbitals and energy levels around the nucleus of an atom/ion.

Question 6

First Ionisation Energy

Answer 6

The removal of one mole of electrons from one mole of gaseous atoms. Factors affecting it include the strength of attraction between the electron and the nucleus, nuclear charge, and atomic radius.

Question 7

Giant Covalent Lattice

Answer 7

A network of atoms bonded by strong covalent bonds (e.g., carbon in diamond, graphite, and graphene). Typically insoluble with high melting and boiling points.

Question 8

Giant Metallic Lattice Structure

Answer 8

The structure of all metals, made up of cations and delocalised electrons. Typically insoluble with high melting and boiling points.

Question 9

Group

Answer 9

A column in the periodic table.

Question 10

Melting Point

Answer 10

The temperature at which a solid melts and becomes a liquid.

Question 11

Metallic Bonding

Answer 11

Strong electrostatic attraction between cations and delocalised electrons.

Question 12

p-block

Answer 12

The part of the periodic table in which the elements have their highest energy electron in a p-orbital.

Question 13

Period

Answer 13

A row in the periodic table.

Question 14

Periodicity

Answer 14

A repeating trend in physical and chemical properties across the periods of the periodic table.

Question 15

s-block

Answer 15

The part of the periodic table in which the elements have their highest energy electron in an s-orbital.

Question 16

Successive Ionisation Energies

Answer 16

The energy required to remove each electron one-by-one from one mole of gaseous atoms/ions.

Question 17

Base

Answer 17

A substance that can accept H+ ions from another substance. Group 2 compounds can be used as bases.

Question 18

Group 2 Oxide

Answer 18

A compound with the general formula MO, where M is a group 2 element.

Question 19

Oxidation

Answer 19

The loss of electrons/increase in oxidation number.

Question 20

Redox

Answer 20

A reaction in which oxidation of one element and reduction of another occurs.

Question 21

Reduction

Answer 21

The gain of electrons/decrease in oxidation number.

Question 22

Second Ionisation Energy

Answer 22

The removal of one mole of electrons from one mole of gaseous 1+ ions to form one mole of 2+ ions.

Question 23

Boiling Point

Answer 23

The temperature at which a liquid boils and becomes a gas.

Question 24

Diatomic Molecules

Answer 24

Molecules that are made up of 2 atoms. Halogens are diatomic.

Question 25

Displacement Reaction

Answer 25

A reaction in which one atom is replaced by another.

Question 26

Disproportionation

Answer 26

The oxidation and reduction of the same element.

Question 27

Induced Dipole-Dipole Interactions

Answer 27

Forces of attraction between molecules caused when the random movement of electrons creates a temporary dipole.

Question 28

London Forces

Answer 28

Another name for induced dipole-dipole interactions.

Question 29

Precipitation Reaction

Answer 29

A reaction in which two aqueous solutions are combined to form an insoluble salt (a precipitate).

Question 30

Water Treatment

Answer 30

The addition of chlorine to water to kill bacteria.

Question 31

Anion

Answer 31

A negatively charged ion.

Question 32

Ammonium Ion

Answer 32

An ion with the formula NH4+. The test for ammonium ions is a reaction with warm NaOH, which forms NH3.

Question 33

Cation

Answer 33

A positively charged ion.

Question 34

Carbonate

Answer 34

A salt containing the CO3^2- anion.

Question 35

Halide

Answer 35

A salt containing a group 7 anion.

Question 36

Qualitative Analysis

Answer 36

Identifies the elements present in a substance, typically using test-tube reactions.

Question 37

Sulfate

Answer 37

A salt containing the anion SO4^2-. A reaction between SO4^2- and Ba^2+(aq) will form a precipitate.

Question 38

Activation Energy

Answer 38

The minimum energy required for a reaction to take place.

Question 39

Average Bond Enthalpy

Answer 39

The energy required to break one mole of gaseous bonds.

Question 40

Endothermic

Answer 40

A reaction which takes in energy (ΔH is positive).

Question 41

Enthalpy (H)

Answer 41

A value that represents the heat content of a system.

Question 42

Enthalpy Change (ΔH)

Answer 42

The change in the heat content of a system during a reaction.

Question 43

Enthalpy Change of Combustion (ΔcH)

Answer 43

The enthalpy change that takes place when one mole of a substance is completely combusted.

Question 44

Enthalpy Change of Formation (ΔfH)

Answer 44

The enthalpy change that takes place when one mole of a compound is formed from its elements.

Question 45

Enthalpy Change of Neutralisation (ΔneutH)

Answer 45

The enthalpy change that takes place when one mole of water is formed from a neutralisation reaction.

Question 46

Enthalpy Change of Reaction (ΔrH)

Answer 46

The enthalpy change that is associated with a particular chemical equation.

Question 47

Enthalpy Profile Diagram

Answer 47

Shows the difference in the enthalpy of reactants and products as well as the activation energy of a reaction.

Question 48

Exothermic

Answer 48

A reaction which gives out energy (ΔH is negative).

Question 49

Hess’ Law

Answer 49

The enthalpy change of a reaction is independent of the route it takes.

Question 50

Standard Conditions

Answer 50

A pressure of 100 kPa and a temperature of 298K.

Question 51

Standard State

Answer 51

The physical state (s, l, g, aq) of a substance under standard conditions.

Question 52

Boltzmann Distribution

Answer 52

A graph showing the distribution of the energies of molecules in relation to the activation energy.

Question 53

Catalyst

Answer 53

A substance that speeds up the rate of a reaction without being used up.

Question 54

Collision Theory

Answer 54

The theory which states that molecules must collide with sufficient energy at the correct orientation for a reaction to occur.

Question 55

Concentration

Answer 55

The amount of a substance that is dissolved per unit volume of solution.

Question 56

Heterogeneous Catalyst

Answer 56

A catalyst that is in a different state to the reactants.

Question 57

Homogeneous Catalyst

Answer 57

A catalyst which is in the same state as the reactants.

Question 58

Pressure

Answer 58

The force that a gas exerts on the walls of a container.

Question 59

Rate of Reaction

Answer 59

A measure of how quickly a reactant is used up/a product is formed.

Question 60

Dynamic Equilibrium

Answer 60

A closed system in which the rates of the forward and reverse reactions are equivalent.

Question 61

Homogeneous Equilibrium

Answer 61

An equilibrium in which all reactants are in the same state.

Question 62

Le Chatelier’s Principle

Answer 62

When a system in dynamic equilibrium is subject to change, the position of equilibrium will shift to minimise the change.

Question 63

KC

Answer 63

The equilibrium constant that is equal to the concentration of products raised to their stoichiometric coefficients divided by the concentration of reactants.