Chapter 4 : Acids And Redox

Question 1

What is a strong acid ?

Answer 1

An acid that releases a large proportion of its H+ ions, it fully dissociates in water

Question 2

What is a weak acid ?

Answer 2

Partially dissociates in water

Question 3

What is an acid ?

Answer 3

Releases H+ ions in solution

Question 4

What is a base - give examples ?

Answer 4

Releases OH- Ions in solution
- metal oxides
- Metal hydroxides
- metal carbonates
- ammonia (NH3)

Question 5

Reaction of acid + metal oxides/carbonates ?

Answer 5

Acid + base = salt + water

Question 6

Acid + metal carbonate ?

Answer 6

Acid + metal carbonate = salt + water + carbon dioxide

Question 7

What is an oxidation number ?

Answer 7

Number of electrons involved in binding to another element

Question 8

State the known oxidation rules

Answer 8

Elements by themselves = 0
Compounds add to total charge

O = -2
H = +1
F = -1
Na/K = +1
Mg/Ca = +2
Cl,Br,I = -1

H in metal hydrides (NaH etc) = -1
O in Peroxides (H2O2) = -1
O bonded to F (F2O) = +2

Question 9

What’s it called when the oxidation number increases ?

Answer 9

Oxidation

Question 10

What’s it called when the oxidation number decreases ?

Answer 10

Reduction