Question

C3H7OH is propanol. Suppose you have 85.9 g sample of propanol. How many carbon atoms are in the sample?

Answer 1

Answer: the answer is 2.58*10^24 atoms

Explanation:

First of all find the molecular formula of propanol i.e. 60g/mol (3*12+7+16+1)

Now ,we have to find the no.of atoms of carbon present in C3H7OH...

We know that 36g of carbon is present in whole sample..

In terms of %

60g=100% {unitary method}

36g=?

i.e. 60%( after calculation)

Now we know that there is 85.9g of sample of propanol in 100% so to find the mass of carbon present in 60% as per above calculation ....

AGAIN UNITARY METHOD

85.9=100%

? = 60%

So...it will be 51.54g

Now, finally to find no.of atoms...by the formula

No.of atoms =no.of moles*Avogadro's no

So putting the values :-

No.of atoms = 51.54/12*6*10^23

No.of atoms = 2.58*10^24