Science, module 5

Question 1

How do atoms react to chemical reactions?

Answer 1

Atoms are rearranged to form new substances.

Question 2

Which is reversible, physical change or chemical reactions?

Answer 2

Physical change

Question 3

Which is usually irreversible, physical change or chemical reactions?

Answer 3

Chemical reactions

Question 4

What are two examples of physical change?

Answer 4

Dissolving and changes of state

Question 5

What are reactants?

Answer 5

Objects/matter that react with one another

Question 6

What are products?

Answer 6

Products are the result of two reactants reacting together

Question 7

In this example, which are the reactants and what is the product?
(Hydrogen + Oxygen = Water)

Answer 7

Reactants = Hydrogen and Oxygen
Product = Water

Question 8

What are 5 possible signs telling you that a chemical reaction is happening?

Answer 8

1. Colour change
2. Fizzing (gas given off)
3. Temperature change
4. Odour (smell)
5. Precipitate formed (cloudy)

Question 9

What are some examples of useful chemical reactions?

Answer 9

1. Making medicines
2. Burning fuels (electricity)
3. Creating building materials and food

Question 10

What is a catalyst?

Answer 10

Added to a reaction to speed up the process.

Question 11

What are the elements (ingredients) of baking powder?

Answer 11

Fumaric acid, a base and sodium carbonate

Question 12

What is the word equation for the chemical reaction baking powder?

Answer 12

Fumaric acid + Sodium carbonate = Sodium fumarate + carbon dioxide + water

Question 13

Tell me 3 things about chemical reactions.

Answer 13

They make new substances,
Usually cannot be reversed,
atoms rearrange and join together differently and may transfer energy to and from surroundings

Question 14

Tell me three things about physical change.

Answer 14

Does not make new substances,
can be reversed,
movement changes but particles don’t change and may transfer energy to and from surroundings

Question 15

What are hydrocarbons made of?

Answer 15

Hydrogen and Carbon

Question 16

What are hydrocarbons?

Answer 16

Compounds

Question 17

What is kerosene a mixture of?

Answer 17

Hydrocarbons

Question 18

What is an example of hydrocarbons found in kerosene?

Answer 18

Decane

Question 19

Burning is a special type of oxidation reaction called…?

Answer 19

Combustion

Question 20

What is the chemical formula for decane?

Answer 20

C10H22

Question 21

What is the substance created in chemical reactions?

Answer 21

Products

Question 22

What are diesel and petrol mixtures of?

Answer 22

Hydrocarbons

Question 23

What is one of the hydrocarbons in petrol?

Answer 23

Octane

Question 24

What is the chemical formula for octane?

Answer 24

C8H18

Question 25

What causes climate change?

Answer 25

Carbon dioxide

Question 26

What is the periodic symbol for nitrogen monoxide?

Answer 26

NO

Question 27

What is the product of the reaction from nitrogen and oxygen from the surrounding air?

Answer 27

Nitrogen Monoxide Gas

Question 28

What are some examples of replacements of petrol and diesel?

Answer 28

1. Electric cars 2. Biofuels

Question 29

What (in equations) does an arrow mean?

Answer 29

'to make' or =

Question 30

What does a balanced equation mean?

Answer 30

an equal amount of atoms on both sides of the equation

Question 31

What is the conservation of mass?

Answer 31

When the total mass of reactants is the total mass of the products. (Reactants mass is same as Products mass)

Question 32

Why would a mass increase?

Answer 32

Due to atoms being added from a gas

Question 33

Why would mass decrease?

Answer 33

Due to atoms being arranged to form a gas that have escaped

Question 34

What are state symbols?

Answer 34

Tells you the state of matter of each substance

Question 35

What does (s) stand for?

Answer 35

Solid

Question 36

What does (l) stand for?

Answer 36

Liquid

Question 37

What does (g) stand for?

Answer 37

Gas

Question 38

What does (aq) stand for?

Answer 38

Dissolved in water

Question 39

Why do we burn fossil fuels?

Answer 39

To produce electricity or drive cars

Question 40

Is burning fossil fuels non-renewable or renewable?

Answer 40

Non-renewable

Question 41

What does it mean when something is endothermic?

Answer 41

Something that transfers energy FROM the surroundings

Question 42

What does it mean when something is exothermic?

Answer 42

Something that transfers energy TO the surroundings

Question 43

What are some examples of exothermic reactions?

Answer 43

Freezing, condensing and dissolving some substances

Question 44

What are some examples of endothermic reactions?

Answer 44

Condensing, subliming, melting and some neutralisation reactions

Question 45

What does SO4 stand for?

Answer 45

Sulfate

Question 46

What does CO3 stand for?

Answer 46

Carbonate

Question 47

What does NO3 stand for?

Answer 47

Nitrate

Question 48

What does OH stand for?

Answer 48

Hydroxide

Question 49

If the formulae ends on a single element, what does the product name end up with?

Answer 49

Ide, at the end

Question 50

What does CaSO4 stand for?

Answer 50

Calcium sulphate

Question 51

What does Na2CO3 stand for?

Answer 51

Sodium carbonate

Question 52

What does KNO3 stand for?

Answer 52

Potassium nitrate

Question 53

What does KOH stand for?

Answer 53

Potassium hydroxide

Question 54

What does MgCl2 stand for?

Answer 54

Magnesium chloride

Question 55

What does lithium + Oxygen make?

Answer 55

Lithium oxide

Question 56

What does C3H8 stand for?

Answer 56

propane

Question 57

What is the chemical formula for paracetamol?

Answer 57

C8 H9 NO2

Question 58

What are the two reactants of Paracetamol?

Answer 58

Aminophenol and ethanoic anhydride

Question 59

What are the two products of Paracetamol?

Answer 59

Paracetamol and Ethanoic acid

Question 60

What is the unit for energy?

Answer 60

Joules (J)