2020 Phase-2 Some Basic Concepts of ChemistryDetermination of Avogadro's number Medium Question 18 of 49 in Some Basic Concepts of Chemistry

One mole of carbon atom weighs 12 g, the number of atoms in it is equal to, (Mass of carbon-12 is $1.9926\times10^{-23}$ g)

A $6.022\times10^{23}$
B $1.2\times10^{23}$
C $6.022\times10^{22}$
D $12\times10^{22}$

The answer is A.

Solution

Number of atoms in 12 g of carbon-12 $=\dfrac{12\ g}{1.9926\times10^{-23}\ g}\approx6.022\times10^{23}$, which is Avogadro's number.

Concept Determination of Avogadro's number

Some Basic Concepts of Chemistry in past papers

49 questions from this chapter have appeared across 23 exam years.