Q26 of 60 Page 1

A student prepared 20% sodium hydroxide solution in a beaker to study saponification reaction. Some observations related to this are given below:

(I) Sodium hydroxide solution turns red litmus blue


(II) Sodium hydroxide readily dissolves in water


(III) The beaker containing solution appears cold when touched from outside


(IV) The blue litmus paper turns red when dipped into the solution


The correct observations are:

Sodium hydroxide is a base it readily dissolves in water to form alkaline solution, that turns red litmus paper blue. When dissolved in water a large amount of heat is evolved leading to exothermic reaction, thus the beaker should be hot outside.

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Hard water is not available for an experiment. Some salts are given below:

(I) Sodium chloride


(II) Sodium sulphate


(Ill) Calcium chloride


(IV) Calcium sulphate


(V) Potassium chloride


(VI) Magnesium sulphate


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(I) Testa


(II) Plumule


(III) Radicle


(IV) Cotyledon


(V) Tegmen


Out of these the actual parts of the embryo are: