Day 129: CBSE Class 10 Science

1. A.
   Both (A) and (R) are true and (R) is the correct explanation of (A).
2. B.
   Both (A) and (R) are true, but (R) is not the correct explanation of (A).
3. C.
   (A) is true, but (R) is false.
4. D.
   (A) is false, but (R) is true.

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1. A.
   Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
2. B.
   Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
3. C.
   Assertion (A) is true, but Reason (R) is false.
4. D.
   Assertion (A) is false, but Reason (R) is true.

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1. A.
   Mg is a lighter element than water.
2. B.
   Mg reacts with water to produce $\mathrm{H_2}$ gas which helps in floating.
3. C.
   Mg reacts with water to produce $\mathrm{N_2}$ gas which helps in floating.
4. D.
   Mg reacts with water to form $\mathrm{CO_2}$ gas which helps in floating.

Tap an option to check your answer.