Question

How many moles are represented by 9.34 x 1021 sodium atoms

a. 1.25x10^2 moles

b. 1.55x10^3 moles

c. 1.55x10^2 moles

d. 1.55 moles

Answer 1

1.55×10⁻² moles of sodium

Step-by-step explanation:

Given data:

Number of atoms of sodium = 9.34×10²¹ atoms

Number of moles of sodium = ?

Solution:

Avogadro number:

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance. The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ atoms

9.34×10²¹ atoms × 1 mol / 6.022 × 10²³ atoms

1.55×10⁻² mol