Sawaal
20
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion(A)  : Graphite is slippery and used as a lubricant. 

Reason (R)    : Graphite has free electrons. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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:   B) Both A and R are true but R is NOT the correct explanation of A.



Explanation:

Graphite possesses a layer structure with two successive layers held by weak forces and able to slide over one another. So, graphite is slippery and this property finds its use as a lubricant. In graphite, each carbon atom is linked to three other carbon atoms while one electron in the carbon atom is delocalised. So, graphite has free electrons 

 

 

Subject: Assertion and Reason
Related Questions
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion(A) :  A little gap is left between iron rails. 

Reason (R)   :  Iron expands in summer. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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 & Explanation Answer: A) Both A and R are true and R is the correct explanation of A.

Explanation:

Iron expands in summer. So, gaps are left between rails to allow for expansion. 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

6 9016
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion (A)  : Carbon dioxide turns lime water milky. 

Reason (R)     : Carbon dioxide sullies the water. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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 & Explanation Answer: C) A is true but R is false.

Explanation:

Carbon dioxide reacts with lime water (calcium hydroxide) to form milky precipitate of calcium carbonate 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

2 10615
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion(A) :  Bangladesh imports jute from India. 

Reason (R)   :  Bangladesh has most of the jute mills. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but R is NOT the correct explanation of A.
C) A is true but R is false. D) Both A and R are false.
 
Answer & Explanation Answer: D) Both A and R are false.

Explanation:

When Bangladesh was created after partition of India, the areas of jute production went to Bangladesh while the jute mills were left in India. So, India imports raw jute from Bangladesh. 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

26 13027
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion (A) : Himalayas once laid under the sea. 

Reason (R)    : Fossils of marine creatures are traced on the Himalayas. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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 & Explanation Answer: A) Both A and R are true and R is the correct explanation of A.

Explanation:

Himalayas are the young fold mountains that at one time are believed to lie inside the Tethys sea. This is evident from the recovery of fossils of marine creatures on its peaks. 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

5 9650
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

 Assertion (A) :  Clothes are not washed properly in hard water. 

 Reason (A)    :  Hard water contains many minerals. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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 & Explanation Answer: B) Both A and R are true but R is NOT the correct explanation of A.

Explanation:

Clothes are not washed properly in hard water because it does not form lather with soap. However, it is true that hard water contains many minerals. 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

1 8812
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion (A)  :   Red colour of blood is due to haemoglobin. 

Reason (R)     :  Haemoglobin is a red pigment. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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 & Explanation Answer: A) Both A and R are true and R is the correct explanation of A.

Explanation:

Haemoglobin is the blood pigment that imparts red colour to the blood. 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

3 9202
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion (A)  : Cotton is grown in alluvial soils. 

Reason (R)    :  Alluvial soils are very fertile. 

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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 & Explanation Answer: A) Both A and R are true and R is the correct explanation of A.

Explanation:

Alluvial soils comprising of silt and sand carried down by the rivers, are very fertile. However, cotton is grown in black soil that suits its mineral requirements 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

7 10033
Q:

Directions : For the Assertion (A) and Reason (R) below, choose the correct alternative 

Assertion (A) :  Gandhiji withdrew the non-cooperation movement 

Reason (R)    :  There was violence at the Chauri Chaura outrage

A) Both A and R are true and R is the correct explanation of A. B) Both A and R are true but 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 & Explanation Answer: A) Both A and R are true and R is the correct explanation of A.

Explanation:

Gandhiji withdrew the non-cooperation movement because of the violence in the Chauri Chaura outrage. 

 

 

Report Error

View Answer Report Error Discuss

Filed Under: Assertion and Reason

4 9634