Chem keywords

Question 1

C3.3 proton number

Answer 1

= atomic number. Number of protons in the nucleus of an atom

Question 2

C3.3 nucleon number

Answer 2

= mass number. Total number of protons & neutrons in the nucleus of an atom

Question 3

C3.3 isotopes

Answer 3

atoms of the same element which have the same proton number but a different nucleon number

Question 4

C3.4 formation of ions

Answer 4

electron loss or gain

Question 5

C3.4 lattice structure (of ionic compounds)

Answer 5

regular arrangement of alternating positive and negative ions

Question 6

C4.1 relative atomic mass (Ar)

Answer 6

average mass of naturally occurring atoms of an element on a scale where the 12C atom has a mass of exactly 12 units

Question 7

C4.1 relative molecular mass (Mr)

Answer 7

sum of the relative atomic masses (used for ionic compounds)

Question 8

C4.2 mole

Answer 8

specific number of particles called Avogadro’s constant

Question 9

C5.1 electrolysis

Answer 9

breakdown of an ionic compound when molten or in aqueous solution by the passage of electricity

Question 10

C6.1 endothermic

Answer 10

bond breaking

Question 11

C6.1 exothermic

Answer 11

bond forming

Question 12

C7.2 redox

Question 13

C7.2 oxidising agent

Answer 13

substance which oxidises another substance during a redox reaction

Question 14

C7.2 reducing agent

Answer 14

substance which reduces another substance during a redox reaction

Question 15

C9.4 transition elements

Answer 15

collection of metals having high densities, high melting points, forming coloured compounds, and which, as elements and compounds, often act as catalysts

Question 16

C9.5 noble gases

Answer 16

unreactive, monoatomic gases

Question 17

C10.1 alloys

Answer 17

mixtures of a metal with other elements

Question 18

C10.1 metallic bonding

Answer 18

lattice of positive ions in a ‘sea of electrons’

Question 19

C11.2 composition of clean air

Answer 19

mixture of 78% nitrogen, 21% oxygen, small quantities of noble gases, water vapour, carbon dioxide

Question 20

C11.2 common pollutants in air

Answer 20

carbon monoxide, sulfur dioxide, oxides of nitrogen

Question 21

C11.2 source of carbon monoxide

Answer 21

incomplete combustion of carbon-containing substances

Question 22

C11.2 source of sulfur dioxide

Answer 22

combustion of fossil fuels which contain sulfur compounds (leading to acid rain)

Question 23

C11.2 source of oxides of nitrogen

Answer 23

car engines

Question 24

C11.3 co2 and methane are..

Answer 24

greenhouse gases

Question 25

C11.3 formation of carbon dioxide

Answer 25

product of complete combustion of carbon-containing substances, product of respiration, product of the reaction between an acid and a carbonate, product of thermal decomposition of calcium carbonate

Question 26

C14.4 alkanes

Answer 26

saturated hydrocarbons whose molecules contain only single covalent bonds

Question 27

C14.4 properties of alkane

Answer 27

generally unreactive, except in terms of burning

Question 28

C14.5 alkenes

Answer 28

unsaturated hydrocarbons whose molecules contain one double covalent bond

Question 29

C14.5 cracking is..

Answer 29

a reaction that produces alkenes

Question 30

C14.7 polymers

Answer 30

long chain molecules formed from small units (monomers)

Question 31

C3.3 isotopes have..

Answer 31

same properties due to same number of electrons in their outer shell

Question 32

C9.1 periodic table

Answer 32

method of classifying elements and its use to predict properties of elements

Question 33

C10.4 uses of aluminium

Answer 33

aircraft parts bc of its strength and low density, food containers bc of its resistance to corrosion

Question 34

C14.3 Homologous series (of alkanes & alkenes)

Answer 34

families of compounds with the same general formula & similar chemical properties