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Model Paper 2 — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryModel Paper 21 Mark
MCQ
Assertion (A): In 285cm there are 3 significant figures.
Reason (R): Zero preceding to first non-zero digit are not significant.
  • A
    Both A and R are true and R is the correct explanation of A.
  • ✓
    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

Correct option: B.
Both A and R are true but R is not the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A .
Explanation: All non-zero digits are significant. For example, in 285 cm , there are three significant figures and in 0.25 mL , there are two significant figures.

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