Ethanol and Ethanoic Acid MCQs

Q1. What is the effect of adding concentrated nitric acid to water?

• A.The temperature of the solution decreases
• B.The temperature of the solution remains the same
• C.The temperature of the solution increases
• D.It causes the glass container to break

Answer: C. The temperature of the solution increases

Going back to the NCERT chapter, The dissolution of acid in water is an exothermic process, which means that the temperature of the solution increases. That fits the listed correct option directly - The dissolution of acid in water is an exothermic process. Quickly on the wrong ones: option A) 'The temperature of the solution decreases' fails since The dissolution of acid in water is an exothermic process; option B) 'The temperature of the solution remains the same' is wrong because The dissolution of acid in water is an exothermic process. Hence the answer is C) The temperature of the solution increases.

Q2. What is the function of the acid present in the stinging hair of nettle leaves?

• A.It acts as a natural antiseptic
• B.It attracts pollinators
• C.It causes pain and irritation
• D.It has no function in the plant

Answer: C. It causes pain and irritation

What is the textbook's take? The acid in nettle stinging hair causes pain and irritation. Does that line up with one of the options? Yes - Methanoic acid causes burning pain. And the rest? option A) 'It acts as a natural antiseptic' is incorrect: Acid causes burning pain, not prevents infection; option B) 'It attracts pollinators' doesn't hold - Acid causes pain, not attracts bees. Pick: C) It causes pain and irritation.

Q3. A few drops of phenolphthalein indicator are added to a sodium hydroxide (basic) solution. What is the colour of the solution?

• A.Pink
• B.Colourless
• C.Blue
• D.Red

Answer: A. Pink