Question

Question 1.30 What will be the mass of one 12C atom in g?

Class XI Some Basic Concepts of Chemistry Page 24

Answer 1

1 mole of carbon= 6.022x 1023 carbon atoms = 12 g carbon
Or 6.022x 1023 atoms of carbon = 12 g of carbon
Therefore 1 atoms of carbon = 12/6.022x 1023 x 1= 1.993 x 10-23 g of carbon

Answer 2

we know,
mass of 1 mole of ¹²C = 12g
and 1 mole of ¹²C = 6.022 × 10²³ atoms of ¹²C
so, mass of 6.022 × 10²³ atoms of ¹²C = 12g
$\therefore\:mass\:of\:one\:atom=\frac{12g}{6.022\times\:10^{23}}\\\\=1.9927\times\:10^{-23}g$

$2^{nd } \: \: method$

Mass of 1 atom of ¹²C = atomic mass of C/Avogadro's constant
= 12g/6.022 × 10²³ g
= 1.9927 × 10^-23 g