Types of Reactions

Question 1

Describe a combination reaction

Answer 1

Where two elements or compounds combine to form one product

Question 2

Describe a displacement reaction

Answer 2

One element takes he place of another element in a reacting compound

Question 3

Describe a decomposition reaction

Answer 3

One substance is split into into two substances

Question 4

Describe a precipitation reaction

Answer 4

Two elements in reactants take the place of each other and a solid (precipitate) forms in one of products

Question 5

Describe a neutralisation reaction

Answer 5

An acid reacts with a base to form a metal salt and either water, carbon dioxide, or hydrogen

Question 6

What are

Answer 6

1. They are liquids.
2. If concentrated they can be corrosive.
3. Acids taste sour (for example, vinegar).
4. Turn blue litmus paper red
5. Usually react with metals to form salts.
6. Acids contain hydrogen ions.
7. Turn Universal Indicator from green to red, and have a pH less than 7.

Question 7

Properties of bases

Answer 7

1. They have a pH higher than 7
2. They turn universal indicator from green to blue/purple
3. They are either oxide donators or hydroxide for alkalis
4. They taste bitter

Question 8

What is an alkali

Answer 8

A special type of base that reacts with water or an acid to release hydroxide ions

Question 9

Acid + metal 》

Answer 9

Metal salt + hydrogen

Question 10

Acid + alkali 》

Answer 10

Metal salt + water

Question 11

Acid + metal oxide 》

Answer 11

Metal salt + water

Question 12

Acid + carbonate 》

Answer 12

Metal salt + water + carbon dioxide