21.(a) Identify the compound of calcium which is yellowish white powder is used in disinfecting drinking water.
(b) write chemical name and formula for the above compound.
(c) write chemical equation involved in manufacturing of this compound.
(d) write two other uses of this compound.
22. (a) write balanced chemical equation for the chlor alkaly process.
(b) why is it called the chlor alkaly process?
23. (a) White powder is added while baking breads and cakes which makes them soft and fluffy. Name this powder.
(b) Name ingredients of this powder.
(c) Explain function of each ingredient.
(d) Write the chemical reaction taking place when this powder is heated during baking.
Answers
21.(a) Identify the compound of calcium which is yellowish white powder is used in disinfecting drinking water.
(b) write chemical name and formula for the above compound.
(c) write chemical equation involved in manufacturing of this compound.
(d) write two other uses of this compound.
The compound is bleaching powder (CaOCl2). Its chemical name is calcium oxychloride. It is manufactured by reaction of solid slaked lime with dry chlorine gas. Ca(OH)2 +Cl2 → CaOCl2 +H2O (i) It is used as disinfectant. (ii) It is used for preparation of Chloroform.
22.(a)write balanced chemical equation for the chlor alkaly process.
(b)why is it called the chlor alkaly process?
The process is called the chlor-alkali process because of the products formed- chlor for chlorine and alkali for sodium hydroxide. ... 2NaOH (aq) + Cl2 (g) + H2 (g) Chlorine gas is liberated at the anode while hydrogen gas is liberated at the cathode