Question

How many 204pb atoms are present in a piece of lead weighing 230 mg ? the percent natural abundance of 204pb is 1.4%?

Answer 1

Answer:-
`9.50*10^1^8atoms` of Pb-204.

Solution:- From given info, the percent natural abundance of Pb-204 is 1.4%. It means, 1.4 grams of Pb-204 are present in 100 grams sample. With the help of this, we could calculate the amount of Pb-204 present in 230 mg that is 0.23 grams sample as:

`0.23gSample((1.4gPb^2^0^4)/(100gSample))`

= 0.00322 g of Pb-204

Let's convert grams to moles and then atoms as:

`0.00322gPb((1mol)/(204g))((6.02*10^2^3atoms)/(1mol))`

=
`9.50*10^1^8atoms` of Pb-204

So, there would be
`9.50*10^1^8atoms` of Pb-204 present in the sample.