Acids, Bases and Salts

Question 1

What is defined as an acid?

Answer 1

An acid is a substance that produces H+ ions when dissolved in water.

Question 2

What is the general word equation for the reaction between acids and metals?

Answer 2

acid + metal -> salt + hydrogen

Question 3

Why can’t calcium react fully with dilute sulfuric acid?

Answer 3

Calcium sulfate is insoluble. The reaction results in a layer of calcium sulfate coated around calcium, preventing it from further reaction.

Question 4

What is the general word equation for the reaction between acids and carbonates?

Answer 4

acid + carbonate -> salt + water + carbon dioxide

Question 5

What is the general word equation for the reaction between acid and base?

Answer 5

acid + base -> salt + water

Question 6

What is defined as an alkali?

Answer 6

An alkali is a soluble base that produces OH- ions in water.

Question 7

What is the general word equation for the reaction between base and ammonium salt?

Answer 7

base + ammonium salt -> salt + ammonia + water

Question 8

What defines a strong acid?

Answer 8

A strong acid is an acid that ionises completely in water to produce a large amount of H+ ions. This leads to a smaller pH value.

Question 9

What is a basic oxide?

Answer 9

Basic oxides are metal oxides that react with acids only.

Question 10

What is an acidic oxide?

Answer 10

Acidic oxides are non-metal oxides that react with alkalis only.

Question 11

What are amphoteric oxides?

Answer 11

Amphoteric oxides are metal oxides that react with both acids and alkalis.

Question 12

What are neutral oxides?

Answer 12

Neutral oxides are non-metal oxides that do not react with acids or alkalis.

Question 13

What are the three amphoteric oxides?

Answer 13

Zinc oxide, aluminium oxide, lead oxide

Question 14

Which 5 common salts are insoluble?

Answer 14

Sulfates: Calcium, Lead, Barium
Chloride: Silver, Lead

Question 15

When do we use titration to prepare salts?

Answer 15

When both the reactants, as well as the product, is an aqueous solution.

Question 16

In titration, why is the solution slowly left to cool after being heated to saturation?

Answer 16

This allows bigger crystals to form.

Question 17

When do we use the adding excess method to prepare salts?

Answer 17

When one of the reactants is an insoluble carbonate or base.

Question 18

In the adding excess method, which reactant is added in excess?

Answer 18

The insoluble carbonate or base; this ensures that all acid has been reacted

Question 19

When do we use the precipitation method to produce salts?

Answer 19

When the product of the salt is insoluble. The reactants also have to meet the following requirements:

• Both must be aqueous
• Can only be salt + salt, or salt + acid

Question 20

What are the three essential conditions for the Haber process?

Answer 20

450˚C - Moderate speed of reaction and yield
200 atm - Moderate yield and cost
Finely divided iron catalyst