Question

Calculate the number of moles of HCl present, if there are 3.01 x 10 to the power 23 HCl molecules.
(a) 2 moles
(b) 0.5 moles
(c) 36.5 moles
(d) 3 moles

Answer 1

Here it is given that there are 3.01 × 10²³ molecules of HCl

We have to find the number of moles

Now, we know that 1 mole has 6.02 × 10²³ molecules

6.02× 10²³ molecules = 1 mole

∴3.02× 10²³ molecules = $\frac{3.02\times 10^{23} }{6.02\times 10^{23}}$

                                      = $\frac{1}{2}$

                                       = 0.5 moles

So, 3.01 × 10²³ molecules of HCl will make 0.5 mole

The correct answer will be option b.

Answer 2

From the question the correct option is b) $0.5 moles$

As we know that,

Given:

The molecules of HCl 3.01 × 10²³  

Find out :

The number of moles.

Let us:

molecules of HCl 3.01 × 10²³

1 mole = 6.02 × 10²³ molecules

so,

6.02× 10²³ molecules = 1 mole

Therefore,

3.02× 10²³ molecules = 3.02×10²³ /6.02× 10²³  

                                     = 1/2

                                      = 0.5 moles