Module 3 Keywords

Question 1

Periodicity

Answer 1

The repeating trends in properties of the elements

Question 2

First ionisation energy

Answer 2

The energy required to remove an electron from each atom in one gaseous mole of an element to make one gaseous mole of 1+ ions

Question 3

Second ionisation energy

Answer 3

The energy required to remove an electron from each ion in one gaseous mole of 1+ ions an to make one gaseous mole of 2+ ions

Question 4

Metallic bond

Answer 4

Electrostatic force of attraction between delocalised electrons and the positive metal cation

Question 5

Covalent bond

Answer 5

Strong electrostatic force of attraction between a shared pair of electrons and the nuclei of the bonded atoms

Question 6

Ionic bond

Answer 6

Electrostatic force of attraction between two oppositely charged ions

Question 7

Reducing agent

Answer 7

A reagent that gives electrons to another species, reducing that species

Question 8

Oxidising reagent

Answer 8

A reagent that takes electrons from another species, oxidising that species

Question 9

Reduction

Answer 9

Gain

Question 10

Oxidation

Answer 10

Loss

Question 11

Disproportionate reaction

Answer 11

When the same element is both ox and red

Question 12

The chemical system

Answer 12

Atoms molecules or ions making up the chemicals

Question 13

System

Answer 13

Chemicals, the reactants and products

Question 14

Surroundings

Answer 14

The apparatus the lab and everything tat isn’t the chemical system

Question 15

Universe

Answer 15

Everything. Both the surrounding and the universe

Question 16

Exothermic

Answer 16

When the energy released making new bonds is larger than the energy absorbed breaking the old bonds
Negative delta h
Chemical system loses energy
Surroundings gains energy
Temperature of surroundings increase

Question 17

Endothermic

Answer 17

When the energy released making new bonds is smaller than the energy absorbed breaking the old bonds.
Positive delta h
Chemical system gains energy
Surroundings loose energy
Temperature of surroundings decrease

Question 18

Activation energy

Answer 18

Minimum energy required to initiate a reaction by the breaking of bonds

Question 19

Standard conditions

Answer 19

Standard pressure of 100Kpa
Standard temperature of 298K
Standard concentration (for solutions only) 1moldm3
Standard state

Question 20

Standard state

Answer 20

Physical state of a substance under standard conditions of 100Kpa and 298K

Question 21

Standard enthalpy change of reaction

Answer 21

The enthalpy change that accompanies a reaction in the molar quantities shown in the chemical equation under standard conditions with all products and reactants in their standard states

Question 22

SECF

Answer 22

The enthalpy change that takes place when one mole of a compound is formed from its elements under standard conditions with all products and reactants in their standard states

Question 23

SECC

Answer 23

The enthalpy change that takes place when one mole of a substance is reacts completely in excess oxygen under standard conditions with all products and reactants in their standard states

Question 24

SECN

Answer 24

The enthalpy change that accompanies the reaction of an acid by a base to make one mole of water under standard conditions with all products and reactants in their standard states

Question 25

Specific heat capacity

Answer 25

The temperature required to raise 1g of a substance by 1K

Question 26

Average bond enthalpy

Answer 26

The energy required to break one mole of a specified type of bond in a gaseous molecule. *value depends on chemical environment

Question 27

Rate of reaction

Answer 27

The change in concentration of the product or reactants in a given time

Question 28

Homogeneous catalyst

Answer 28

Is in the same physical state as the REACTANTS

Question 29

Heterogeneous catalyst

Answer 29

Is in a different physical state as the REACTANTS

Question 30

Adsorption

Answer 30

Substance is weakly bonded to the surface of the catalyst

Question 31

Desorption

Answer 31

Product molecules leave the surface of the catalyst

Question 32

Absorption

Answer 32

Substance is weakly bonded within the the catalyst

Question 33

Dynamic equilibrium

Answer 33

Closed system Concentrations are constant Rates are equal

Question 34

Catalyst

Answer 34

Provides an alternate pathway for the reaction to happen with a lower activation energy, increasing the proportion of molecules with sufficient energy to react.