Question

7. Assertion (A): The reaction of calcium with water is less violent in comparison to that of sodium.
Reason (R): The heat evolved is not sufficient for the hydrogen to catch fire.
a) Both A and Rare true and R is the correct explanation of A.
b) Both A and Rare true and R is not the correct explanation of A.
c) A is true but R is false
d) If both A and Rare false.
8. Assertion(A):Zinc can easily displace copper on reacting with a solution of copper sulphate.
Reason(R):Copper is more reactive metal as compared to Zinc.
a) Both A and Rare true and R is the correct explanation of A.
b) Both A and Rare true and R is not the correct explanation of A.
c) A is true but R is false
d) If both A and Rare false.
9. ASSERTION (A):Arteries are thick walled and elastic in nature.
REASON (R) :Arteries have to transport blood away from the heart.
a) Both A and Rare true and R is the correct explanation of A.
b) Both A and Rare true and R is not the correct explanation of A.
c) A is true but R is false
d) If both A and Rare false.
10.ASSERTION (A) :The purpose of making urine is to filter out undigested food from intestine.
REASON (R) :Kidneys filter the waste and produce urine.
a) Both A and Rare true and R is the correct explanation of A.
b) Both A and Rare true and R is not the correct explanation of A.
c) A is true but R is false
d) A is False but R is True.

Answer 1

Answer:

7) b

8) c

9) b

10) b

hope it's right

I don't know the correct answer

Answer 2

Assertion and Reasoning

Explanation:

7. Assertion (A): The reaction of calcium with water is less violent in comparison to that of sodium.

Reason (R): The heat evolved is not sufficient for the hydrogen to catch fire.

• Both Assertion and reason is true and Reason is the correct explanation of A

• Sodium reacts violently with cold water and forms sodium hydroxide and hydrogen gas. So, the hydrogen gas produced during this reaction catches fire.

• Calcium reacts with cold water and forms hydrogen and calcium hydroxide.
• The heat produced in this reaction is less. So, it is not sufficient to ignite the hydrogen gas formed. Hence, the reaction of calcium metal with water is less violent compared to sodium.

8. Assertion(A):Zinc can easily displace copper on reacting with a solution of copper sulphate.

Reason(R):Copper is more reactive metal as compared to Zinc.

• Both assertion and reason is true and reason is the correct explanation of assertion
• Reactivity series is to predict the reaction of metals. In a compound, a less reactive metal is displaced by a more reactive metal. Zinc is a more reactive metal than copper, so zinc displaces copper from copper sulfate.

9. ASSERTION (A):Arteries are thick walled and elastic in nature.

REASON (R) :Arteries have to transport blood away from the heart.

• Both assertion and reason is true but reason is not the correct explanation of assertion.

• Arteries are blood vessel that is a vital part of the circulatory system. Arteries transport blood from the heart to different organs of the body. Blood releases from the heart under high pressure. To resist high pressure, arteries have a thick wall and are elastic.

10.ASSERTION (A) :The purpose of making urine is to filter out undigested food from intestine.

REASON (R) :Kidneys filter the waste and produce urine.

• Assertion is false and reason is true
• Different life processes are carried out in the body. Each life process produces a lot of waste in the body. Accumulation of waste may be harmful to the body. The kidney plays a role in eliminating the waste from the blood and produce urine.