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प्रश्न
While studying saponification reaction for the preparation of soap, a teacher suggested to a student to add a small quantity of common salt to the reaction mixture. The function of common salt in this reaction is to
(A) reduce the alkalinity of the soap
(B) reduce the acidity of the soap
(C) enhance the cleansing capacity of soap
(D) favour precipitation of soap
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उत्तर
Common salt is added in saponification reaction, as it helps in the precipitation of soap by decreasing the solubility of soap.
Hence, the correct option is D.
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संबंधित प्रश्न
In an experiment to study the properties of ethanoic acid, a student takes about 3 mL of ethanoic acid in a dry test tube. He adds an equal amount of distilled water to it and shakes the test tube well. After some time he is likely to observe that
(A) a colloid is formed in the test tube.
(B) the ethanoic acid dissolves readily in water.
(C) the solution becomes light orange.
(D) water floats over the surface of ethanoic acid.
List two uses of esters.
When you add a few drops of acetic acid to a test-tube containing sodium bicarbonate powder, which one of the following is your observation?
(A) No reaction takes place
(B) A colourless gas with pungent smell is released with brisk effervescence
(C) A brown coloured gas is released with brisk effervescence
(D) Formation of bubbles of a colourless and odourless gas
The substance which can produce brisk effervescence with baking soda solution is:
(a) ethanol
(b) vegetable oil
(c) vinegar
(d) soap solution(b) hydrocarbon ends directed towards the centre and ionic ends directed outwards
In a soap micelle, the soap molecules are arranged radially with the hydrocarbon ends, i.e. hydrophobic, directed towards the centre; and, ionic ends, i.e. hydrophilic, directed outwards.
An organic compound A (molecular formula C2H4O2) reacts with Na metal to form a compound B and evolves a gas which burns with a pop sound. Compound A on treatment with an alcohol C in the presence of a little of concentrated sulphuric acid forms a sweet-smelling compound D (molecular formula C3H6O2). Compound D on treatment with NaOH solution gives back B and C. Identify A, B, C and
Ethanol can be oxidized to ethanoic acid. Write the equation and name the oxidizing agent.
If you take a pinch of sodium hydrogen carbonate powder in a test-tube and add drop-by-drop acetic acid to it, what would you observe immediately? List any two main observations.
What type of compound is formed by the reaction between acetic acid and an alcohol?
Choose the correct answer:
Select the acid which contains four hydrozen atoms in it.
Give the balanced chemical equation of the following reaction:
Evolution of carbon dioxide by the action of ethanoic acid with NaHCO3.
