How many chlorine atoms are present in 15.5 g of CCl4?

Question

I have an answer of 2.43E23 atoms, which I have yet to get. Any help is great! Thanks

Answer 1

First, determine moles of CCl4; you'll have 4 x that amount of chlorine, then use Avagadro's number to get answer.

15.5g/[12.01 + (4 x 35.45)] = 0.101moles

CCl4; so,

4 x 0.101moles x 6.02 x 10^23 atoms =

2.43 x 10^23 atoms of Cl

Answer 2

Chlorine Atoms

Answer 3

How many chlorine atoms are present in 15.5 g of CCl4?

Answer: 2.43E23 atoms.

For finding out the number of atoms in certain grams of a compound, you should first find out the molar mass. As you know 1mole of any substance (atoms, ions, molecules) contains Avogadros' no. of that substance (atoms, ions, molecules). So first obtain the molar mass.
Molar mass of CCl4 = 1x12 + 4x35.5 =154 grams
154 grams of CCl4 contains 6.022 x 10^23 no of molecules
1 gram of CCl4 contains = 6.022 x 10^23/154 no of molecules
15.5 grams of CCl4 contains = (6.022 x 10^23/154) x 15.5 no of molecules = 0.6062 x 10^23

Now, we got the total no. of Molecules of CCl4, but we have to find Total no of Cl atoms in the same mass.

As one molecule of CCl4 contains one Carbon atom (C) and four Chlorine atoms (Cl), hence the no. of Chlorine atoms will be four times the no of Carbon atoms or the total no of molecules. So total no. of Chlorine atoms in 15.5 grams of CCl4 = 4 x 0.6062 x 10^23 = 2.43 x 10^23 atoms
or 2.43E23 atoms.

Answer 4

Mol.Wt. of CCl4 = 154 gms.
154 gms f CCl4 contains 4 gm atoms of chlorine
15.5 g of CCl4 shall contain =(15.5/154)*4 gm atoms of Cl
1 gm atom of any compound contains 6.023*10^23 atoms
Therefore, 15.5/154*4 gm atoms of Chlorine will contain
=(15.5/154)*4*6.023*10^23 atoms
or =2.424844 *10^23 atoms
or =2.43E23 atoms.