Acid & Redox

Question 1

In aqueous solution, acids release…

Answer 1

In aqueous solution, acids release H+ ions (protons)

Question 2

Hydrochloric acid (strong acid)

Answer 2

HCl

Question 3

Sulfuric acid (strong acid)

Answer 3

H₂SO₄

Question 4

Nitric acid (strong acid)

Answer 4

HNO₃

Question 5

Ethanoic acid (weak acid)

Answer 5

CH₃COOH

Question 6

Bronsted-lowry base

Answer 6

Proton (H+ ion) acceptor

Question 7

Bronsted-lowry acid

Answer 7

Proton (H+ ion) donor

Question 8

Strong acids…

Answer 8

• Strong acids completely dissociate in aqueous solution.
• means they release all their hydrogen atoms into the solution as H+ ions.

Eg: HCl(aq)→ H⁺(aq) + Cl⁻(aq)

Question 9

Weak acids…

Answer 9

• Weak acids partially dissociate in aqueous solution.
• means they release a small proportion of their available hydrogen atoms into solution as H+ ions.

Eg: CH3COOH(aq) ⇌ H+(aq) + CH3COO¯(aq)

Question 10

common bases:

Answer 10

metal oxides, metal hydroxides, metal carbonates, ammonia

Question 11

Alkali

Answer 11

Alkali = A soluble base that releases OH¯ in aqueous solution.

Question 12

Potassium hydroxide (alkali)

Answer 12

NaOH

Question 13

Potassium hydroxide (alkali)

Answer 13

KOH

Question 14

Aqueous ammonia

Answer 14

NH3

Question 15

A base readily…

Answer 15

A base readily accepts H+ ions from an acid.

Question 16

OH¯ ions readily accept a H+ ion forming…

Answer 16

OH¯ ions readily accept H+ ions forming H2O

Question 17

NH3 readily accepts a H+ ion forming…

Answer 17

NH3 readily accepts a H+ ion forming an NH4+ ion

Question 18

Magnesium oxide

Answer 18

MgO

Question 19

Calcium oxide

Answer 19

CaO

Question 20

Copper oxide

Answer 20

CuO

Question 21

Sodium carbonate

Answer 21

Na2CO3

Question 21

Calcium carbonate

Answer 21

CaCO3

Question 22

Copper carbonate

Answer 22

CuCO3

Question 23

What happens in the neutralisation of an acid?

Answer 23

In the neutralisation of an acid, the H+ ions from the acid react with OH¯ ions from a basse forming water. A salt is also formed as the H+ ion of the acid is replaced by a metal ion or ammonium ion from base.

Question 24

Acid + Base

Answer 24

Acid + Base → Salt + Water

Question 25

Acid + Metal Carbonate

Answer 25

Acid + Metal Carbonate → Salt + Carbon Dioxide + Water

Question 26

Observations of carbonate reactions:

Answer 26

• In carbonate reactions,
• there will be effervescence due to the CO2 produced.
• CO2 gas is evolved and the solid carbonate will dissolve.

Question 27

Dissociation of sulfuric acid (H2SO4)

Answer 27

• H2SO4 is a strong acid.
• This is only true for 1 of the 2 hydrogen atoms.
• When sulfuric acid is mixed with water each H2SO4 molecule dissociates,
• Releasing only 1 of its 2 hydrogen atoms as H+ ions.
  H2SO4(aq) →H+(aq) + HSO4-
  -The resulting HSO4-(aq) ions then only partially dissociate.
  HSO4-(aq) ⇌ H+(aq) + SO4-
• Sulfuric acid first behaves as a strong acid then the HSO4-(aq) ions formed behave as a weak acid