reactions group 2 and group 7

reaction with water

reaction with water

metals react with water to form a metal hydroxide and hydrogen gas

M + 2H2O → M(OH)2 + H2

solubility of metal hydroxides

increase down the group

solubility of metal sulphates

decreases down the group

extraction of titanium

1. Tio2 converted to TiCl4 by heating it with carbon in a stream of chlorine gas

2. purification via fractional distillation

3. reduction by magnesium at 1000°C

   TiCl4 + Mg2 → 2MgCl + Ti

removal of SO2 from flu gas

1. CaO + 2H2O + SO2 → CaSO3 + 2H2O

2. CaCO3 +2H2O +SO2 → CaSO3 +2H2O + CO2

making bleach

2NaOH + Cl2 → NaClO +NaCl + H2O

reaction of chlorine in water

H2O + Cl2 ←→ Cl- + ClO- + 2H+

decomposition of chlorine and water in sunlight

H2O + Cl2 ← → 2Cl- + 1/2 O2 + 2H+

Sodium halide reaction with h2so4

NaX + H2SO4 → HX +NaHSO4

reduction of HX

Cl and F cant be reduced

2HX + H2SO4 → 2H2O + X2 + SO2