Acids and Bases

Question 1

acid

Answer 1

A substance capable of producing hydrogen ions in solution (Arr)
or donating a hydrogen ion (BL)

Question 2

acid-base reaction

Answer 2

A reaction in which an acid reacts with a base

Question 3

acid rain

Answer 3

Rainwater that has reacted with acidic emissions and has a pH less that 5.5

Question 4

acidic solution

Answer 4

An aqueous solution in which the concentration of Hydrogen ions (H+) is greater than the concentration of hydroxide ions (OH-)
At 25 C , pH < 7

Question 5

acidification

Answer 5

An increase in atmospheric carbon dioxide concentrations causing an increase in the acidity of the oceans.

Question 6

acidity

Answer 6

The concentration of H+ ions in an aqueous solution.

Acidity is measured in the pH scale

Question 7

alkali

Answer 7

A SOLUBLE base or solution of a soluble base.

Question 8

Arrhenius Model

Answer 8

A model that defines an acid as a substance that ionises water to produce H+ ions and a base as a substance that dissociates in water to form OH- ions.

Question 9

Base

Answer 9

A substance capable of producing hydroxide ions in solution (Arr)
A substance that can accept a proton (BL)

Question 10

Basic solution

Answer 10

An aqueous solution in which [H+] < [OH-]
I.e. the concentration of OH - is higher than H+.
pH > 7

Question 11

Bronsted- Lowry Model

Answer 11

A compound that transfers a proton is an acid

A compound that accepts the proton is a base.

Question 12

diprotic acid

Answer 12

An acid that can ionise in water to give 2 H+ ions.

Question 13

dissociation

Answer 13

A process in which molecules or ionic compounds separate or split into smaller particles such as atoms or ions.
E.g. NaCl — Na+ + Cl-

HCl —- H+ + Cl-

Question 14

hydroxide ion

Answer 14

OH- ion.

Question 15

indicator

Answer 15

A substance that is different colours in its acid and base forms.

Question 16

ionisation

Answer 16

1. The removal of one or more electrons from an atom or ion.

2. The reaction of a molecular substance with a solvent (usually water) to form ions in solution.

Question 17

limewater test

Answer 17

A test for carbon dioxide.

Bubbles gas through a solution of calcium hydroxide Ca(OH)2. The limewater turns milky with CO2.

Question 18

Limiting reagent

Answer 18

A reactant that is completely consumed in a reaction and which determines the amount of products formed.

Question 19

Monoprotic acid

Answer 19

An acid molecule that generates only one hydrogen ion when ionized in water.

Question 20

What taste does an acid have?

Answer 20

Sour

Question 21

diprotic acid

Answer 21

an acid that ionizes to give 2 protons per molecule

Question 22

triprotic acid

Answer 22

an acid that ionizes to give 3 protons

Question 23

electrolyte

Answer 23

a substance that ionizes/dissociates to give ions in solution

Question 24

Neutralization

Answer 24

A reaction of an acid and a base to give salt and water.

Question 25

Why did Arrhenius theory need to be improved?

Answer 25

It did not explain: a. Why some substances that don't contain hydrogen ions (protons) can still make acidic solutions. SO2 and CO2 b. Why some substances that don't contain hydroxide ions still make a basic solution. NH3

Question 26

Strong acid

Answer 26

Completely dissociates/ionizes in water. e.g. HCl, H2SO4 HNO3

Question 27

Strong base

Answer 27

Completely dissolves in water to give hydroxide ions e.g. NaOH

Question 28

Weak acid

Answer 28

An acid that does NOT completely ionize in water. e.g. vinegar - ethanoic acid does not completely ionize.

Question 29

Weak base

Answer 29

A base that does not completely ionize in water to make hydroxide ions

Question 30

Concentration - dilute vs concentrated.

Answer 30

Dilute - a small amount of solute dissolved in solvent Concentrated - a large amount of solute dissolved in solvent

Question 31

pH scale

Answer 31

a logarithmic scale that measures the concentration of hydrogen ions range is 0 7 14 acid neutral base pH = -log10 [H+]

Question 32

Acid + Carbonate

Answer 32

salt + water + carbon dioxide

Question 33

Acid + Hydrogencarbonate

Answer 33

salt + water + carbon dioxide

Question 34

acid + metal

Answer 34

salt + hydrogen gas

Question 35

Salt

Answer 35

A metal ion and negative ion | Usually made from replacing the hydrogen ion/s in an acid

Question 36

Test for carbonate salts

Answer 36

1. Add acid to salt 2. Bubble gas produced through limewater Ca(OH)2 3. Solution of limewater will go cloudy if gas is CO2. Ca(OH)2 + CO2 = CaCO3 (s) + H2O

Question 37

Reactive metal

Answer 37

A metal that reacts easily with acids to make hydrogen gas. e.g. calcium, magnesium, sodium NOT gold, silver, copper

Question 38

Reaction of ammonia with water

Answer 38

NH3 + H2O = NH4 + + OH-

Question 39

How could you distinguish between and acid and a base using litmus paper?

Answer 39

An acid turns indicator red | A base turns indicator blue

Question 40

spectator ions

Answer 40

ions that do not participate in a chemical reaction

Question 41

Ionization

Answer 41

When a substance reacts with water to make ions