topic 8.1, 8.2, and 18.1 - Acids and bases

Question 1

lewis acid

Answer 1

electron pair acceptor (accepts electrons / loses protons)

Question 2

lewis base

Answer 2

electron pair donator

Question 3

brønsted lowry acid

Answer 3

proton donator

Question 4

brønsted lowry base

Answer 4

proton acceptor

Question 5

acid

Answer 5

a substance that ionises in water to form hydrogen ions (H⁺).

Question 6

alkali

Answer 6

a soluble base that ionises in water to form hydroxide ions (OH⁻).

Question 7

how protic an acid is

Answer 7

monoprotic acids - form only one hydrogen ion (HCl)
diprotic acid - forms two hydrogen ions (H₂SO₄)
triptotic acid - forms three hydrogen ions (H₃PO₄)

Question 8

conjugate acids and bases

Answer 8

When an acid reacts with a base, the first acid in the equation is referred to as the conjugate acid 1. After it loses the H⁺ ion it becomes a conjugate base (1).

When a base reacts with an acid, the first base in the equation is referred to as the conjugate base 2. After it gains the H⁺ ion it becomes a conjugate acid (2).

The conjugate bases/acids are named 1/2

CA1 + CB2 -> CB1 + CA2
H₂CO₃ + OH⁻ -> HCO₃⁻ + H₂O

Question 9

Amphiprotic species

Answer 9

Can act as a brønsted lowry base or brønsted lowry acid.

Amino acids are amphiprotic - the carboxyl group can act as an acid and the amine group can act as a base.

Water, amino acids, HCO₃⁻, HSO₄⁻, H₂PO₄⁻

Question 10

Properties of acid

Answer 10

Taste - sour
pH - <7
pOH - >7
Litmus paper - red
Phenolphthalein - colourless
Methyl orange - red

Question 11

Properties of bases

Answer 11

Taste - bitter
pH - >7
pOH - <7
Litmus paper - blue
Phenolpthalein - pink
Methyl orange - yellow

Question 12

acid + metal

Answer 12

acid (aq) + metal (s) -> salt (aq) + hydrogen (g)

H₂SO₄ (aq) + Fe (s) -> FeSO₄ (aq) + H₂ (g)

Question 13

acid + base

Answer 13

acid (aq) + base (aq) -> salt (aq) + water (l)

H₂SO₄ (aq) + CaO (aq) -> CaSO₄ (aq) + H₂O (l)

Question 14

acid + metal carbonate

Answer 14

acid + metal carbonate -> salt + water + carbon dioxide

2HCl (aq) + Na₂CO₃ (s) -> 2NaCl (aq) + H₂O (l) + CO₂ (g)

Question 15

acid + metal hydrogencarbonate

Answer 15

acid + hydrocarbonate -> salt + water + carbondioxide

HCl (aq) + NaHCO₃ (s) -> NaCl (aq) + H₂O (l) + CO₂ (g)

Question 16

Amphoteric

Answer 16

Can act as a lewis base or lewis acid.

Differs from amphiprotic as H⁺ ions are not needed to act as an acid/base (electron pairs donated)

ZnO is an example - can act as an acid despite not having H⁺ ions