Question

calculate the number of calcium ions in 5.6g of calcium oxixe

Answer 1

5.6 gram calcium means 5.6/56 = 0.1 moles of Calcium oxide.

1 mole Calcium oxide = 1 mole calcium ion
Then 0.1 mole calcium oxide = 0.1 mole calcium ion.

Or 0.1 * Avagaro No. Of ions = 6.022 * 10^22

Answer 2

Given:

Substance = Calcium Oxide

Quantity of the substance = 5.6g

To find:

The number of calcium ions in Calcium Oxide

Solution:

Number of moles of CaO

= 5.6g /56

= 0.099 mol

= 0.1 mol

Number of moles in 1  mol CaO = 6.022 × 10^ 23

These are atoms of Ca ion.

Therefore in 0.1 mol there will be -  

= 0.1 x 6.022 × 10^23

= 6.022 × 10^22

Answer: The number of calcium ions in Calcium Oxide is  6.022 × 10^22 atoms