Advertisements
Advertisements
Question
While studying the saponification reaction, what do you observe when you mix an equal amount of colourless vegetable oil and 20% aqueous solution of NaOH in a beaker?
(A) The colour of the mixture has become dark brown
(B) A brisk effervescence is taking place in the beaker
(C) The outer surface of the beaker has become hot
(D) The outer surface of the beaker has become cold
Solution
While studying saponification reaction, when equal amount of colourless vegetable oil and 20% aqueous solution of NaOH in mixed in a beaker, the beaker becomes hot. This is because, saponification is an exothermic reaction.
Hence, the correct answer is option The outer surface of the beaker has become hot.
APPEARS IN
RELATED QUESTIONS
Explain the formation of scum when hard water is treated with soap.
What are the raw materials required for making soap in a laboratory (or at home)?
What is a detergent? Name one detergent.
What is saponification? Write the chemical equation of the reaction involved in this process. Name all the substances which take part in this process and also those which are formed.
In a soap micelle, the soap molecules are arranged radially with:
(a) ionic ends directed towards the centre and hydrocarbon ends directed outwards
(b) hydrocarbon ends directed towards the centre and ionic ends directed outwards
(c) both ionic ends and hydrocarbon ends directed toward the centre
(d) both hydrocarbon ends and ionic ends directed outwards
The chemical which is not required for the preparation of soap in the laboratory is:
(a) vegetable oil
(b) baking soda
(c) caustic soda
(d) common salt
Explain the action of soap in removing an oily spot from a piece of cloth.
Answer the following question.
In three test tubes A, B, and C, three different liquids namely, distilled water, underground water and distilled water in which a pinch of calcium sulphate is dissolved, respectively are taken. Equal amount of soap Answer is added to each test tube and the contents are shaken. In which test tube will the length of the foam (lather) be longest? Justify your answer.
Explain why often coloured spots are formed on clothes during washing.
______ molecules go and join with dirt and oil in the cloth.
