No.14. How the insoluble salts are prepared?
Answer. In this method, usually solutions of soluble salts are mixed. During the reaction exchange of ionic radicals take place to produce two new salts. One of the salts is insoluble and the other is soluble. The insoluble salt precipitates (solidify in solution). For example,
AgNO3 NaCl AgCl + NaNO3
Q.No.15. Why a salt is neutral, explain with an example?
Answer. A salt formed by the total replacement of ionization H+ ions of an acid by a positive metal ions or NH4+ ion is called normal or neutral salt. It is neutral as it does not consist of H+ and OH- ions. As a result, it does not give or OH- ions on ionization in water.
HCl(aq) + KOH(aq) KCl(aq) + H2O
KCl is neutral salt
Q.No.16. Name an acid used in the preservation of food.
Answer: Benzoic acid is used in the preservation of food.
Q.No.17. Name the acids present in:
Answer. i. Vinegar ii. Ant sting iii. Citrus fruit iv. Sour milk
- Acetic acid is present in vinegar.
- Formic acid is present in ant sting.
- Citric acid is present in citrus fruit
- Lactic acid is present in sour milk
Q.No.18. How can you justify that CHCOOK is a basic salt?
Answer. When potassium acetate is dissolved in water it form acetic acid which is weak acid and potassium hydroxide a strong base that’s why it is basic salt.
CH3COOK + H2O CH3COOH +KOH