Key Concepts

Question 1

What are spectator ions?

Answer 1

Ions that are unchanged in reactions

Question 2

What is an ion?

Answer 2

A charged particle

Question 3

What is an isotope?

Answer 3

Atoms of an element with the same number of protons but a different number of neutrons

Question 4

How was Mendeleev’s version of the periodic table different to today’s version?

Answer 4

Some pairs of elements were the wrong way around (for example, iodine and tellurium), also there were gaps left for atoms that hadn’t yet been discovered

Question 5

What is a cation?

Answer 5

A positively charged ion

Question 6

What is an anion?

Answer 6

A negatively charged ion

Question 7

What is the charge of a zinc ion?

Answer 7

2+

Question 8

What is the charge of a copper ion?

Answer 8

2+

Question 9

What is the charge of a silver ion?

Answer 9

1+

Question 10

What are the possible charges of an iron ion?

Answer 10

2+ (II) 3+ (III)

Question 11

What is the charge of an ammonium ion?

Answer 11

1+

Question 12

What is the charge of a nitrate (NO3) ion?

Answer 12

1-

Question 13

What is the charge of a sulfate ion?

Answer 13

2-

Question 14

What is the charge of a carbonate(CO3) ion?

Answer 14

2-

Question 15

What is the charge of a hydroxide ion?

Answer 15

1-

Question 16

If ions have different numbers of charges what do you do to find out the formula of the compound that they form?

Answer 16

Times them together/ find the LCM

Question 17

What are ionic bonds?

Answer 17

Strong electrostatic forces of attraction between oppositely charged ions

Question 18

What structure do ionic compounds have?

Answer 18

Lattice structure which has a regular arrangement of ions

Question 19

Do ionic compounds have high or low melting and boiling points?

Answer 19

High

Question 20

What state are ionic compounds in at room temperature?

Answer 20

Solid

Question 21

Are the majority of ionic compounds soluble or insoluble in water?

Answer 21

Soluble

Question 22

What is a covalent bond?

Answer 22

A covalent bond is a bond between two atoms where a pair of electrons are shared between the two atoms

Question 23

What is a simple molecular substance?

Answer 23

Molecules consisting of only a few atoms

Question 24

What type of bonding do simple molecular substances have?

Answer 24

Covalent

Question 25

What state are simple molecular substances usually in at room temperature?

Answer 25

Liquid or gas

Question 26

Do simple molecular substances have high or low melting and boiling points?

Answer 26

Low

Question 27

What happens to the bonds/forces in simple molecular substances when they change state

Answer 27

The intermolecular forces are overcome but the covalent bonds do not break

Question 28

Do simple molecular substances usually conduct electricity in solution?

Answer 28

No, however some simple molecular substances break down when in solution and form ions. The ions are free to move around so the solution conducts electricity (only when ions are formed)

Question 29

Are simple molecular substances usually soluble in water?

Answer 29

No, they are usually insoluble because the intermolecular forces between the substance and the water are usually weaker than the intermolecular forces between the water molecules and between the molecules of the substance itself

Question 30

When are simple molecular forces soluble?

Answer 30

When the simple molecular substance can form strong enough intermolecular forces with the water molecules

Question 31

What is a giant molecular substance?

Answer 31

Molecules containing many atoms

Question 32

What bonding do giant molecular substances have?

Answer 32

Covalent

Question 33

What structure do giant molecular substances have?

Answer 33

Regular lattice structure

Question 34

Do giant molecular substances usually have high or low boiling and melting points?

Answer 34

High

Question 35

What state are giant molecular substances usually in at room temperature?

Answer 35

Solid

Question 36

What type of model do you use to represent a giant molecule?

Answer 36

Ball and stick

Question 37

Give some examples of giant molecular substances

Answer 37

• Graphite
• Diamond
• Graphene
• Fullerenes

Question 38

Why can graphene conduct electricity?

Answer 38

Non-bonding outer electrons become delocalised and are free to move through the structure

Question 39

What structure do metals have?

Answer 39

Giant lattice of positively charged metal ions

Question 40

What are metallic bonds?

Answer 40

Strong electrostatic forces of attraction between positively charged metal ions and delocalised electrons

Question 41

Are metals usually soluble or insoluble in water?

Answer 41

Insoluble

Question 42

What happens if a force is applied to a metal?

Answer 42

Layers of positively charged ions slide over each over and the metal changes shape without shattering

Question 43

How do you calculate empirical formula?

Answer 43

• Divide the mass by relative formula mass
• Divide both answers by the smallest answer
• If there are fractions then multiply both answers to make sure there are no fractions

Question 44

What is a closed system?

Answer 44

A situation where no substances can enter or leave during a reaction

Question 45

What is a non-enclosed/open system?

Answer 45

A situation where substances can enter or leave during a reaction

Question 46

What is the law of conservation of mass?

Answer 46

The mass of the reactants and products stays the same during a chemical reaction, the total mass of the substances involved is the same before and after a reaction

Question 47

What does it mean when a reactant is in excess?

Answer 47

There will be some left over when the reaction is complete