Acids, Bases & Salts

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Topic 10: ACIDS, BASES & SALTS

Bases are named like any ionic compound, the name of the metal ion first (with a Roman numeral if necessary) followed by “hydroxide”.

Fe(OH)2 (aq) = iron (II) hydroxide

Fe(OH)3 (aq) = iron (III) hydroxide

Al(OH)3 (aq) = aluminum hydroxide

NH3 (aq) is the same thing as NH4OH:

NH3 + H2O  NH4OH

Also called ammonium hydroxide.

جمعرات، 28 ربیع الثانی، 1438

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Formula Writing of Bases

Topic 10: ACIDS, BASES & SALTS

Formula writing of bases is the same as for any ionic formula writing. The charges of the ions have to cancel out.

Calcium hydroxide = Ca+2 and OH-1 = Ca(OH)2 (aq)

Potassium hydroxide = K+1 and OH-1 = KOH (aq)

Lead (II) hydroxide = Pb+2 and OH-1 = Pb(OH)2 (aq)

Lead (IV) hydroxide = Pb+4 and OH-1 = Pb(OH)4 (aq)

Lithium hydroxide =

Copper (II) hydroxide =

Magnesium hydroxide =

جمعرات، 28 ربیع الثانی، 1438

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Physical Properties of Acids & Bases

Topic 10: ACIDS, BASES & SALTS

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ACIDS

Acids taste sour (e.g. vinegar, lemon juice).

Acids are harmful to living cells.

Aqueous solutions of all acids contain hydrogen ions.

Acid turns blue litmus red.

Strong acids are corrosive.

BASES

Alkalis are taste bitter

Strong alkalis are corrosive.

Aqueous solutions of all alkalis contain hydroxide ion.

Alkalis turns red litmus blue.

Soapy touch.

جمعرات، 28 ربیع الثانی، 1438

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Chemical Properties of Acids

Topic 10: ACIDS, BASES & SALTS

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With metals

Metals above copper in the reactivity series will react with acids, giving off hydrogen gas, forming a salt.

Mg(s) + H2SO4(aq)  MgSO4(aq) + H2(g)

With bases (metal oxides and hydroxides)

The base dissolves in the acid and neutralises it. A salt is formed.

H2SO4(aq) + CuO(s)  CuSO4(aq) + H2O(l)

With metal carbonates

With metal carbonates, effervescence occurs, salt, water and carbon dioxide gas is produced.

2HCl(aq) + CaCO3(s)  CaCl2(s) + H2O(l) + CO2(g)

جمعرات، 28 ربیع الثانی، 1438

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Neutralization