Question

plzz tell me what is the no. of ions in this -

Answer 1

Solution :-

We have to find out the number of ions present in 3gm of $CO_{3}^{2-}$

First of all we should know what is ion ?

» Ion is nothing but a atom or a molecule which have a net charge ≠ 0 upon it.

Now we know :-

Mass of

Carbon (C) = 12 u

Oxygen (O) = 16 u

So mass of $CO_{3}^{2-}$

= 12(1) + 16(3)

= 12 + 48

= 60 u

So molar mass of $CO_{3}^{2-}$

= 60 u × $N_A$

= 60 g

Now we will find out the number of Moles of $CO_{3}^{2-}$ .

$No. \: Of\: Moles = \dfrac{Given\: mass}{Molar\: mass}$

$= \dfrac{3}{60}$

$= \dfrac{1}{20}\: Moles$

Now as we know there are $N_A$ No of Particles in one mole of any substance.

Also $N_A = 6.022 \times 10^{23}$

So Number of ions present in 1/20 moles of $CO_{3}^{2-}$ .

$= \dfrac{1}{20} \times 6.022 \times 10^{23}$

$= \dfrac{1}{2} \times 6.022 \times 10^{22}$

$= 3.011 \times 10^{22}\: \textsf{ No of ions}$