1.5 Symbols, Formulae And Equations

Question 1

What is the general word equation for the reaction of a reactive metal and water ?

Answer 1

Metal (s) + Water (l) > Metal Hydroxide (aq) + Hydrogen (g)

Question 2

What is the general word equation for a less reactive metal reacting with water ?

Answer 2

Metal (s) + steam (g) > Metal oxide (s) + Hydrogen

Question 3

What is the general word equation for a metal reacting with an acid ?

Answer 3

Metal (s) + acid (aq) > Salt (aq) + Hydrogen (g)

Question 4

What is the general word equation for neustralisation reactions ?

Answer 4

Acid (aq) + Base/alkali (aq) > Water (l)

Question 5

What is the general word equation for a thermal decomposition reaction; the breakdown of a substance using heat ?

Answer 5

Metal Carbonate (s) > Metal Oxide (s) + Carbon dioxide (g)

Question 6

What is the general word equation for halogen displacement reactions ?

Answer 6

Chlorine (aq) + Potassium Bromide (aq) > Potassium Chloride (aq) + Bromine (aq)

Question 7

What are some of the common acids ?

Answer 7

Hydrochloric acid
Sulfuric acid
Nitric acid
Ethanoic acid

Question 8

What is the chemical formulae of hydrochloric acid?

Answer 8

HCl

Question 9

What is the chemical formulae of Sulfuric acid?

Answer 9

H²SO⁴

Question 10

What is the chemical formulae of Nitric acid ?

Answer 10

HNO³

Question 11

What is the chemical formulae of ethanoic acid?

Answer 11

CH³COOH

Question 12

What are some common alkalis and bases ?

Answer 12

Potassium hydroxide - KOH - Alkali
Sodium hydroxide - NaOH - Alkali
Ammonia - NH³ - Alkali
Magnesium Oxide - MgO - base
Calcium Carbonate - CaCO³ - base
Sodium Hydrogen Carbonate - NaHCO³ - base

Question 13

What is a base ?

Answer 13

A base is a substance that reacts with an acid producing a salt and water

Question 14

What is an alkali ?

Answer 14

An Alkali is a soluble base

Question 15

What is the chemical formulae of the base, magnesium oxide ?

Answer 15

MgO

Question 16

What is the chemical formulae of the base Calcium Carbonate ?

Answer 16

CaCO³

Question 17

What is the chemical formulae of sodium hydrogen carbonate?

Answer 17

NaHCO³

Question 18

What is the chemical formulae of potassium hydroxide ?

Answer 18

KOH

Question 19

What is the chemical formulae of the alkali sodium hydroxide

Answer 19

NaOH

Question 20

What is the chemical formulae of the alkali Ammonia ?

Answer 20

NH³

Question 21

Write the word equation for the thermal decomposition of copper carbonate ?

Answer 21

Copper carbonate > Copper Oxide + Carbon Dioxide
Metal Carbonate > Metal oxide + Carbon Dioxide

Question 22

Write the word equation for the reaction between sodium hydroxide and hydrochloric acid ?

Answer 22

Sodium hydroxide+ hydrochloric acid > sodium chloride + water
Alkali/base + acid > salt + water

Question 23

Write the word equation for the reaction of magnesium when heated in oxygen ?

Answer 23

Magnesium + oxygen > Magnesium Oxide

Question 24

Write the word equation for the reaction of bromine with a solution of sodium iodide ?

Answer 24

Bromine + Sodium Iodide > Sodium Bromide + Iodine

Question 25

Write the word equation for the reaction of sodium with water ?

Answer 25

Sodium + water > sodium hydroxide + hydrogen

Question 26

Write the word equation for the reaction of magnesium and steam

Answer 26

Magnesium+ steam > Magnesium Oxide + Hydrogen

Question 27

What is magnesium oxide ?

Answer 27

A base

Question 28

What is Calcium Carbonate?

Answer 28

A base

Question 29

What is Sodium hydrogen carbonate?

Answer 29

A base

Question 30

What is a molecular ion?

Answer 30

A charged particle made up of two or more atoms covalently bonded together

Question 31

What is an element?

Answer 31

An element is a substance which consists of only one type of atom and it cannot be broken down into simpler substances by chemical means

Question 32

What are the state symbols?

Answer 32

Solid (s) Liquid (l) Gas (g) Aqueous (aq)

Question 33

What is an aqueous solution?

Answer 33

An aqueous solution forms when a substance is dissolved in water

Question 34

What are examples of acid aqueous solutions ?

Answer 34

HCl (aq) - Hydrochloric acid H²SO⁴ (aq) - Sulfuric acid HNO³ (aq) - Nitric acid

Question 35

What are Alkali aqueous solutions ?

Answer 35

KOH (aq) - Potassium Hydroxide NaOH (aq) - Sodium Hydroxide NH³ (aq) - Ammonia

Question 36

Salts which fform from the reactions of aqueous acids and/or alkalis will also be aqueous i.e a solution of the salt forms - give examples of these

Answer 36

KCl (aq) - Potassium Chloride Na²SO⁴ (aq) - Sodium Sulfate Mg(NO³)² (aq) - Magnesium Nitrate

Question 37

What do ionic equations show only ?

Answer 37

Ionic equations show only the ions involved in the reaction i.e those with a physical state. Ions not involved are called spectator ions

Question 38

What substances can be separated into ions, why and what are the exceptions?

Answer 38

- Only ionic substances can be separated into ions, covalent substances cannot as they do not contain ions - However acids (covalent bonding) are an exception to this rule since they separate into ions in aqueous solution