Calculate the mass, in grams, of 0.433 mole of calcium nitrate

1) 1.51 × 10²³  particles of Mg

2) 0.54 × 10⁻³  moles

Explanation:

Given data:

1)

Number of moles of Mg = 0.250 mol

Number of representative particles = ?

Solution:

The given problem will solve by using 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 mol = 6.022 × 10²³  particles

0.250 mol × 6.022 × 10²³  particles / 1 mol

1.51 × 10²³  particles of Mg

2)

Given data:

Number of moles of lead = ?

Number of atoms of lead = 3.25×10²⁰ atoms

Solution:

The given problem will solve by using 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 mol = 6.022 × 10²³  atoms

1 mol × 3.25×10²⁰ atoms/ 6.022 × 10²³  atoms

0.54 × 10⁻³  moles