Question

the molar mass of calcium is 40 gram what will be the number of calcium atom in 0.4 gram of calcium​

Answer 1

Given:

atomic mass of calcium is 40u.

No. of moles =given weight/molecular weight

No. of Cu moles=0.4/40=1/00=0.01moles

We know that 1 mole of any substance contains 6.023 x 10²³ atoms/ molecules/ions

1mole of Cu contains=6.023 x 10²³ atoms of Cu

0.01 mole of Cu contains =6.023 x10²¹ atoms of calcium.

∴The no. of calcium atoms in 0.4 u of calcium are 6.023 x10²¹ atoms