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Atoms and Molecules — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceAtoms and Molecules2 Marks
Question
Define mole. What are the two things that a mole represents?
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Answer

A group of 6.022 × 1023 particles (atoms, molecules or ions) of a substance is called a mole of that substance. One mole represents the amount of a substance equal to its 'GRAM ATOMIC MASS' or 'GRAM MOLECULAR MASS' and 6.022 × 1023 no. of particles of the substance.

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