Chemical formulae

Question 1

Common acids

Answer 1

•Hydrochloric acid -> HCl
•Sulphuric acid -> H2SO4
•Nitric acid -> HNO3
•Phosphoric acid -> H3PO4
•Ethanoic acid -> CH3COOH

Question 2

Common bases

Answer 2

•Sodium hydroxide -> NaOH
•Potassium hydroxide -> KOH
•Calcium hydroxide -> Ca(OH)2
•Ammonia -> NH3

Question 3

What is an acid?

Answer 3

A proton donor (H+) because hydrogen loses an electron to be an ion it become a singular proton

Question 4

Acids release what?

Answer 4

H+ ions in an aqueous solution

Question 5

What is a strong acid?

Answer 5

It completely dissociates into its ions in an aqueous solution - HCl. Releasing all its acidic hydrogen atoms

Question 6

What is a weak acid?

Answer 6

It partially dissociates into its ions - CH3COOH. Only releases a small proportion of its available hydrogen atoms

Question 7

Exception to the strong acids

Answer 7

Releases 1 of 2 hydrogen atoms

Question 8

What is a base?

Answer 8

When a substance readily accepts H+ ions from an acid. A proton acceptor

Question 9

What is an alkali?

Answer 9

A base that dissolves in water and releases OH- ions in aqueous solutions. Examples: NaOH, KOH, NH4OH

Question 10

What is a salt?

Answer 10

Produced when H+ ions of an acid is replaced by a metal ion or NH4

Question 11

Common acids salts

Answer 11

•Hydrochloric acid - Chloride salt
•Sulphuric acid - Sulphate salt
•Nitric acid - Nitrate salt
•Phosphoric acid - Phosphate salt
•Ethanoic acid - Ethanoate salt

Question 12

Reactions to make salts: Acid + Ammonia?

Answer 12

Acid + Ammonia -> Ammonia salt

Question 13

Reactions to make salts: Acid + Metal oxide?

Answer 13

Acid + Metal Oxide -> Salt + Water

Question 14

Reactions to make salts: Acid + Metal Hydroxide?

Answer 14

Acid + Metal Hydroxide -> Salt + Water

Question 15

Reactions to make salts: Acid + Metal?

Answer 15

Acid + Metal -> Salt + Hydrogen

Question 16

Reactions to make salts: Acid + Carbonate?

Answer 16

Acid + Carbonate -> Salt + Water + Carbon dioxide

Question 17

Solubility of salts: Nitrates

Answer 17

All nitrates are soluble in water

Question 18

Solubility of salts: Sodium, potassium and ammonium

Answer 18

All sodium, potassium and ammonium salts are soluble in water

Question 19

Solubility of salts: Chlorides

Answer 19

All chlorides except silver chloride , AgCl, are soluble in water

Question 20

Solubility of salts: Sulphates

Answer 20

All sulphates are soluble in water, except BaSO4 and AgSO4, which are insoluble

Question 21

Solubility of salts: Carbonates

Answer 21

All carbonates are insoluble in water except AgF, lead (III) iodine is insoluble in water

Question 22

How to recognise acids?

Answer 22

H in-front of compound except CH3COOH

Question 23

How to recognise bases?

Answer 23

End with carbonates, CO3

Question 24

How to recognise salts?

Answer 24

Positive ions of metals and negative non-metals

Question 25

What is empirical formula?

Answer 25

The simplest whole number ratio of each element present in a compound

Question 26

What is molecular formula?

Answer 26

The actual number of atoms of each element in a molecule has

Question 27

Rules of ion formation

Answer 27

•Metals form positive ions, group 1 forms 1+ and group 2 form 2+ •Non-metals form negative ions, group 6 form 2- and group 7 form 1- •Positive ions usually end in ‘-ium’ •Negative ions usually end in ‘-ide’ or ‘-ate’ or ‘-ite’ •Transition metals can form positive ions of variable change •Compound ions contains more than one element

Question 28

Ammonium formulae

Answer 28

NH4+

Question 29

Hydroxide formulae

Answer 29

OH-

Question 30

Nitrate (V) formulae

Answer 30

NO3-

Question 31

Manganite (VII) formulae

Answer 31

MnO4-

Question 32

Carbonate formulae

Answer 32

CO3 2-

Question 33

Sulphate (VI)

Answer 33

SO4 2-

Question 34

Phosphate formulae

Answer 34

PO4 3-