Consider the following statements: 1. All acids are bitter to taste. 2. Bases that are soluble in water are called alkalis. 3. Indicators are substances that change colour in acidic and basic solutions. Which of the statements given above is/are correct?

The correct option is (c). Explanation Acids and bases are distinguished by specific physical properties such as taste and solubility, as well as their chemical interaction with indicators. - Statement 1 is Incorrect: Acids are characterized by a sour taste (e.g., citric acid in lemons). It is bases that are bitter to taste and feel soapy to touch. - Statement 2 is Correct: Bases that are soluble in water are specifically called alkalis (e.g., Sodium Hydroxide). All alkalis are bases, but not all bases are alkalis. - Statement 3 is Correct: Indicators are substances that change colour when placed in acidic or basic solutions, thereby helping to identify the nature of the substance (e.g., Litmus turns red in acid and blue in base). Key Takeaway: Acids taste sour, whereas bases taste bitter. Alkalis are a specific subset of bases that dissolve in water.

Consider the following statements: 1. All… - NCERT Class 7 Science MCQ

NCERT Class 7 Science — Chapter 1: Acids, bases and salts

mcqmedium

Consider the following statements:

All acids are bitter to taste.
Bases that are soluble in water are called alkalis.
Indicators are substances that change colour in acidic and basic solutions.

Which of the statements given above is/are correct?

NCERT textbook question

From NCERT Science - class 7 · Page 45

Options

A1 and 2 only
B2 only
C2 and 3 only
D1, 2 and 3

Did you get this right?

Solution

The correct option is (c).

Explanation

Acids and bases are distinguished by specific physical properties such as taste and solubility, as well as their chemical interaction with indicators.

Statement 1 is Incorrect: Acids are characterized by a sour taste (e.g., citric acid in lemons). It is bases that are bitter to taste and feel soapy to touch.
Statement 2 is Correct: Bases that are soluble in water are specifically called alkalis (e.g., Sodium Hydroxide). All alkalis are bases, but not all bases are alkalis.
Statement 3 is Correct: Indicators are substances that change colour when placed in acidic or basic solutions, thereby helping to identify the nature of the substance (e.g., Litmus turns red in acid and blue in base).

Key Takeaway: Acids taste sour, whereas bases taste bitter. Alkalis are a specific subset of bases that dissolve in water.

Your note

More from Chapter 1: Acids, bases and salts

With reference to the chemical nature of substances, consider the following statements: 1. All substances that taste sour contain acids. 2. Substances that taste bitter and feel soapy on touching are generally acidic in nature. 3. Baking soda is an example of a substance that has a bitter taste and is basic in chemical nature. Which of the statements given above is/are correct?

medium

Consider the following statements regarding the preparation of indicators: 1. Litmus is obtained from a plant called Pitcher plant. 2. Turmeric paper is made by depositing turmeric paste on blotting paper. 3. China rose indicator is prepared by keeping petals in warm water. Which of the statements given above is/are correct?

medium

Which one of the following acids is primarily responsible for the sour taste of unripe mangoes?

easy

With reference to the use of Calamine solution, consider the following statements: 1. It is used to treat skin irritation caused by ant bites. 2. It contains Calcium carbonate. 3. It is applied on the skin to neutralize the effect of wasp stings. Which of the statements given above is/are correct?

medium

Consider the following statements regarding the effect of indicators on common substances: 1. Lemon juice turns red litmus blue. 2. Soap solution turns red litmus blue. 3. Milk of magnesia turns turmeric paper blue. Which of the statements given above is/are correct?

medium

Keep practising Chapter 1: Acids, bases and salts

Work through every question from this NCERT chapter.

Browse all NCERT Class 7 Science chapters