Science 11-12.3

Question 1

acid + alkali = ?

Answer 1

salt+water

Question 2

the word salt is a general term for

Answer 2

a compound containing an element that is a metal.

Question 3

acid + metal = ?

Answer 3

salt + hydrogen

Question 4

How to test for hydrogen gas produced?

Answer 4

Lighted splint test. Will extinguish with a “pop” sound in the presence of hydrogen gas.

Question 5

What are metals that do not react with acids?

Answer 5

Copper, Silver, Gold

Question 6

Acid + Carbonate

Answer 6

salt + carbon dioxide + water

Question 7

Neutralisation occurs when?

Answer 7

An acid is mixed with an alkali.

Question 8

When an acid is mixed with an alkali what is this chemical reaction?

Answer 8

Neutralisation.

Question 9

Different types of Chemical Changes?

Answer 9

• Combustion
• Thermal Decomposition
• Oxidation
• Neutralisation

Question 10

Definition of Combustion? (Chemical Reaction)

Answer 10

Combustion is a chemical reaction in which a substance is heated in the presence of oxygen to form one or more new substances.

• Heat and light energy are often given out during combustion.
• FIRECRACKERS, BURN WOOD

Question 11

Definition of Thermal Decomposition? (Chemical Reaction)

Answer 11

• Thermal Decomposition is the process in which a substance breaks down into two or more SIMPLER substances upon heating.
• e.g. Calcium carbonate –heat–> calcium oxide + carbon dioxide
• HEATING CALCIUM CARBONATE

Question 12

Definition of Oxidation? (Chemical Reaction)

Answer 12

• When a substance gains oxgen, it undergoes a chemical change called oxidation.
• Rusting is an example of oxidation. This process occurs when iron reacts with oxygen and water vapour in the air to form a layer of rust.
• Cellular respiration is an example of oxidation. Glucose, which is a food molecule, is broken down in the presence of oxygen to provide cells with energy to sruvive and reproduce.
• e.g. glucose + oxgen —-> carbon dioxide + water

Question 13

Two examples of oxidation around us?

Answer 13

Rusting and Cellular respiration

Question 14

Reactions of acids? (3 ways)

Answer 14

• Acid + Metal
• Acid + Carbonate
• Acid + Alkaline

Question 15

Define a physical change

Answer 15

• No new substances are formed
• The change can usually be reversed.

Question 16

How do chemical changes occur?

Answer 16

• Heating
• Mixing
• Exposure to light
• Interaction with oxygen

Question 17

Combustion of fuels..

Answer 17

Can produce air pollutants such as carbon monoxide, Sulfur dioxide and Oxides of nitrogen

Question 18

Most alkaline, Least acidic pH colour and number

Answer 18

Dark purple, 14

Question 19

Most acidic, Least alkaline pH colour and number

Answer 19

Red, 0

Question 20

Neutral pH colour and number

Answer 20

Green, 7

Question 21

what is used to test for acidic levels of a substance?

Answer 21

Indicators such as litnus paper. Blue litnus paper turns red when the solution is acidic.

Question 22

Substances that react with one another are known as?

Answer 22

Reactants

Question 23

The new substances formed are known as?

Answer 23

Products

Question 24

What property of the substances does not change even after a chemical change has occured?

Answer 24

The mass of substances

Question 25

predator-prey relationship DRAKE LOLLLL

Answer 25

Predators hunt and kill their prey for food. 1. Speak of the strategies and adaptations predators have in order to succesfully obtain food (hunting techniques and mimicing methods to lure prey) ; 2. Talk about how these prey have adaptations to avoid being caught by their predators. (Effective camouflage, mimic unpleasant objects to deter predators)