Question

Assertion and Reasoning Questions:
(a) Both Assertion and Reason are true and Reason is the correct explanation of the Assertion. (b) Both
Assertion and Reason are true but Reason is not the correct explanation of the Assertion. (c) Assertion is true
but the Reason is false. (d) Both Assertion and Reason are false
11. Assertion: Olfactory indicators are those whose colour changes in acidic and basic medium.
Reason: They react with acidic and basic solutions.
12. Assertion: Active metals react with acids to liberate Hydrogen gas.
Reason: It is an example of displacement reaction.
13. Assertion: Acids contain H+ ions.
Reason: H+ ions neutralise acids
14. Assertion: The process of dissolving an acid or a base in water is a highly exothermic one.
Reason: A large amount of heat is produced.
15. Assertion: On heating, colour of hydrated copper sulphate changes from blue to white.
Reason: Copper sulphate is a crystalline salt.

Answer 1

Answer:

11 d

12 a

13 c

14 a

15 c

All are correct 100%

Answer 2

Assertion and Reasoning

Explanation:

11. Assertion: Olfactory indicators are those whose colour changes in acidic and basic medium.

Reason: They react with acidic and basic solutions.  

• Both Assertion and reason are false

• Indicators are substances whose solutions change color or smell as a result of environmental changes. Olfactory indicators are those that change their smell instead of changing color to help determine whether a given solution is acidic or basic.

• When an acid or base is added to an olfactory indicator, it changes its smell.

• Example: Indicators like onion and vanilla change their smell in acidic solutions but retain their smell in base solutions.  

12.Assertion: Active metals react with acids to liberate Hydrogen gas.

Reason: It is an example of displacement reaction.

• Assertion and Reason are true and reason is the correct explanation of assertion.

• In the reactivity series, the metals above hydrogen such as Zn, Al, Mg, Ca are more reactive than hydrogen so these metals displace hydrogen from dilute acids. This is also called displacement reaction.

13. Assertion: Acids contain H+ ions.

Reason: H+ ions neutralise acids

• Assertion is true and Reason is false

• H+ ions are present in acid and are responsible for its acidic properties.

• Neutralization occurs when an acid and a base react (combine), releasing equal amounts of H+ and OH- ions.

14. Assertion: The process of dissolving an acid or a base in water is a highly exothermic one.

Reason: A large amount of heat is produced.

• Assertion and Reason are true. Reason is the correct explanation of assertion.

• The process of dissolving an acid or a base in water is highly exothermic, as the production of H+ or OH - ions generates a significant amount of heat.

15. Assertion: On heating, colour of hydrated copper sulphate changes from blue to white.

Reason: Copper sulphate is a crystalline salt.

• Both Assertion and Reason are true. Reason is not the correct explanation of assertion.
• When heated, hydrated copper sulfate turns from blue to white, and the crystalline form transforms into amorphous (powder).
• The color change is caused because  water molecules are escaping when heating the copper sulphate, and copper sulfate pentathlete is converted to anhydrous copper sulfate.  
• Copper sulphate is a crystalline salt.