Alkali metals

Question 1

Obtaining of potassium:

Answer 1

KCl(l) + Na(g) → NaCl(s) + K(g)

Question 2

Reaction of alkaline metals with water:

Answer 2

2 Na(s) + 2 H2O(l) → 2 NaOH(aq) + H2(g)

Question 3

Reaction of alkaline lithium with nitrogen:

Answer 3

6 Li(s) + N2(g) → 2 Li3N(s)

Question 4

Reactions of alkaline metals with oxygen:

Answer 4

4 Li(s) + O2(g) → 2 Li2O(s)
2 Na(s) + O2(g) → Na2O2(s)
K(s) + O2(g) → KO2(s)

Question 5

Electrolysis of brine:

Answer 5

2 NaCl(aq) + 2 H2O(l) → Cl2(g) + 2 NaOH(aq) + H2(g)

Question 6

Use of the baking soda:

Answer 6

HCO3–(aq) + HA(aq) → A–(aq) + H2O(l) + CO2(g) Reaction with sodium tartrate:
NaHCO3 + Na[OOCCH(OH)CH(OH)COOH] →
Na2[OOCCH(OH)CH(OH)COO] + H2O + CO2

Question 7

Decomposition of potassium nitrate:

Answer 7

2 KNO3(s) → 2 KNO2(s) + O2(g)