Question

An alloy of Iron (54.7%), nickel (45.0%) and manganese (0.3%) has a density of 8.17 g cm⁻³ ______ × 10²⁶ iron atoms are there in a block of alloy measuring 10.0 cm × 20.0 cm × 15.0 cm.

Options

• 1.44

• 2.97

• 3.24

• 2.41

Answer 1

An alloy of Iron (54.7%), nickel (45.0%) and manganese (0.3%) has a density of 8.17 g cm⁻³ 1.44 × 10²⁶ iron atoms are there in a block of alloy measuring 10.0 cm × 20.0 cm × 15.0 cm.

Explanation:

ρ = `w/"V"`

Volume of block = a³

= 10 × 20 × 15 cm³

ρ = 8.17 g/cm³

`w` = ρ × v

= `(8.17 × 10 × 20 × 15)/100`

= 24510 g

Molecules of Fe = `"Mole of Fe"/"N"_"A"`

= `(24510 × 54.7)/(56 × 100)`

= 1.44 × 10²⁶ atoms