EASY
10th CBSE
IMPORTANT
Earn 100

A remarkable property of acids is that they can 'dissolve' metals. When metals are added to an acid, they disintegrate and disappear into the acid.

In this question, the word 'dissolve' is used within quotes. This is because it is not actually an example of dissolving. What is the main difference between a metal 'dissolving' in an acid and sugar dissolving in water?

Important Questions on Acids, Bases and Salts

MEDIUM
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 17

Sunita carried out the following reactions in the laboratory:

  • Complete neutralisation of one mole of sodium carbonate with hydrochloric acid
  • Complete neutralisation of one mole of sodium bicarbonate with hydrochloric acid

She found that the amount of carbon dioxide formed in both the reactions was the same.

MEDIUM
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 18

Sunita carried out the following reactions in the laboratory:

Complete neutralisation of one mole of sodium carbonate with hydrochloric acid
Complete neutralisation of one mole of sodium bicarbonate with hydrochloric acid

How does the amount of salt formed in case (i) compare with the amount of salt formed in case (ii)?

MEDIUM
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 19

To prepare a salad dressing, Parag adds a solution of sodium chloride in distilled water to vinegar.

State what change will occur in the following:

  • The pH of the vinegar
  • The acidity of the vinegar
MEDIUM
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 20

Rajesh was given a substance and asked to identify it. He conducted three tests on the substance and recorded the results below. (P) It releases carbon dioxide, water, and a sodium salt on heating with water. (Q) It turns universal indicator greenish-blue. (R) It can be prepared from ammonia as a raw material.

What substance was Rajesh given?

EASY
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 21

Rajesh was given a substance and asked to identify it. He conducted three tests on the substance and recorded the results below. (P) It releases carbon dioxide, water, and a sodium salt on heating with water. (Q) It turns universal indicator greenish-blue. (R) It can be prepared from ammonia as a raw material.

Give one use of the substance based on the properties mentioned in P and Q.

MEDIUM
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 22

Rajesh was given a substance and asked to identify it. He conducted three tests on the substance and recorded the results below. (P) It releases carbon dioxide, water, and a sodium salt on heating with water. (Q) It turns universal indicator greenish-blue. (R) It can be prepared from ammonia as a raw material.

Rajesh later read that recrystallisation of the sodium salt formed in P gives another basic salt that is used in manufacture of borax.

Identify the sodium salt formed in P.

MEDIUM
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 23
Aditi finds that a mixture of an acid and a base does not change the colour of either red or blue litmus paper. Compare the amounts of H+ and OH-in the solution. 
HARD
10th CBSE
IMPORTANT
Science Textbook of Competency Based Questions for Class X>Chapter 2 - Acids, Bases and Salts>Exercise>Q 24
pH is measured on a scale of 0 to 14, with lower values indicating high hydrogen ion concentration (more acidic) and higher values indicating low hydrogen ion concentration (less acidic). A pH of 7 is considered as neutral. Every whole unit in pH represents a ten-fold increase in or decrease in hydrogen ion concentration. What would the hydrogen ion concentration of a solution of pH 4 be compared to a solution of pH 8?