Page 133 - ICSE Chemistry 8

Examples:

• Reac on of sodium hydroxide and hydrochloric acid: Sodium hydroxide and dilute hydrochloric
acid react in the form of a solu on to form sodium chloride salt and water.
HCl(aq) + NaOH(aq) NaCl(aq) + H O(l)
2
Hydrochloric acid Sodium hydroxide Sodium chloride Water
• Reac on of potassium hydroxide and sulphuric acid: Potassium hydroxide reacts with dilute
sulphuric acid to form potassium sulphate and water.
H SO (aq) + 2KOH(aq) K SO (aq) + 2H O(l)
2
4
2
2
4
Sulphuric acid Potassium hydroxide Potassium sulphate Water
• Reac on of zinc oxide and nitric acid: Zinc oxide and nitric acid react to produce zinc nitrate and
water.
ZnO(s) + 2HNO (aq) Zn(NO ) (aq) + H O(l)
3
3 2
2
Zinc oxide Dilute nitric acid Zinc nitrate Water
Some more examples of neutralisa on reac on are listed below.
• CuO(s) + dil.H SO (aq) CuSO (aq) + H O(l)
4
2
2
4
Copper(II) oxide Dilute sulphuric acid Copper sulphate Water
• PbO(s) + 2HNO (aq) Pb(NO ) (aq) + H O(l)
2
3 2
3
Lead oxide Dilute nitric acid Lead nitrate Water
• Zn(OH) (s) + H SO (aq) ZnSO (aq) + 2H O(l)
2
4
4
2
2
Zinc hydroxide Sulphuric acid Zinc sulphate Water
Activity 6.6

Aim: To show neutralisa on reac on

Materials required: Some sodium hydroxide, a conical fl ask, a glass dropper, some phenolphthalein
solu on, some dilute hydrochloric acid
Procedure
• Take about 50 mL sodium hydroxide in a
conical fl ask.

• Add 2–3 drops of phenolphthalein solu on
to it. The solu on turns pink.
• Now add dilute hydrochloric acid dropwise HCl
with the help of a glass dropper. Shake well
each me you add a drop.
NaOH +
Observa on: The solu on becomes colourless. phenolphthalein

• Now add a drop of sodium hydroxide
solu on.
The solu on again turns pink.

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