Answer check please!

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]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.


Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Do you multiply by 3 or 2?

Do you multiply by 3 or 2?

Where does the 6.02x10^23

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

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...

Part c that is number of MOLECULES of CO2; each molecule contains 3 atoms (1 C and 2 0).

WebElements: the periodic table on the WWW []

Copyright 1993-20010 Mark Winter [The University of Sheffield and WebElements Ltd, UK]. All rights reserved.