## Answer check please!

**Anonymous**

Just need someone to look my homework over, so I know if I am doing these right.

[b]Find the number of atoms in:[/b]

a) 52.5g of Calcium metal

b) 1.5 mol of Carbon

c) 1.5 mol of Carbon dioxide

[b]Answers:[/b]

[b]a)[/b] Atomic mass of Ca=40.1g

52.5g Ca x 1mol Ca / 40.1g Ca = 1.32mol

1.32 moles of Ca x 6.02x10^23 / 1 mol Ca = [b]7.95x10^23 atoms Ca[/b]

[b]b)[/b] 1.5 moles C x 6.02x10^23 / 1mol C = [b]9.03x10^23 atoms C[/b]

[b]c)[/b] 1.5 moles CO2 x 6.02x10^23 / 1mol C02 = [b]9.03x10^23 atoms C02[/b]

Please let me know if they are right, explaining where I went wrong with wrong answers.

chemhelp (not verified)| 13 June 2007 - 2:58pm## Do you multiply by 3 or 2?

Do you multiply by 3 or 2?

chemhelp (not verified)| 12 June 2007 - 2:35am## Where does the 6.02x10^23

Where does the 6.02x10^23 come from or represent?

llaurr (not verified)| 24 April 2009 - 1:32am## I agree with the 2nd and 3rd

I agree with the 2nd and 3rd answers, but you did the order of operations wrong in the 1st one...

Martin17| 24 October 2005 - 5:43amPart c that is number of MOLECULES of CO2; each molecule contains 3 atoms (1 C and 2 0).