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Physical Chemistry

Language of Chemistry Stoichiometry Atomic Structure Oxidation and Reduction Periodic Table Acid and Base Electronic Theory of Valency Equivalent Weight and Atomic Weight

Physical Chemistry-II

Non-Metals

Inorganic Chemistry

Introduction Compound of Metals Hydroxide Chlorides And Nitrates Sulphates And Carbonates General Metallurgy Sodium and Its Compounds Copper Zinc Iron

Hydroxide

Preparations

i) Alkali metals and alkaline earth metals can form alkali with water.

$N a + 2 H_{2} 0 \to 2 N a O H + H_{2} + ∆$

$C a + 2 H_{2} 0 \to C a (O H)_{2} + H_{2}$

ii) By precipitation with NaOH, insoluble metal hydroxide are prepared.

$F e S O_{4} + 2 N a O H \to F e (O H)_{2} ↓ + N a_{2} S O_{4}$

$N i C l_{2} + 2 N a O H \to N i (O H)_{2} ↓ + 2 N a Cl$

Properties

i) Solubility

-Alkali earth metal hydroxides are sparingly soluble

-Other are insoluble

ii) Action of heat:

-Alkali metal hydroxides are thermally stable except $L i O H$ (thermally unstable).

$2 L i O H \to L i_{2} O + H_{2} O$

-Rest other are thermally unstable i.e. decompose on heating.

$Z n (O H) 2 \to Z n O + H 2 O$

$F e (O H) 2 \to △ F e O + H_{2} O$

iii) Nature of hydroxides:

-Similar to that of respective oxides.