Posted by **Justin** on Tuesday, January 1, 2008 at 1:21pm.

I'm having trouble converting moles to grams and finding the mass of molecules.

Problems I'm stuck on:

What is the mass in grams of .99x10^49 Sodium Chloride Molecules?

and How many moles of Cu are in 9.61 grams?

and How many moles are in 5.94x10^45 Ne atoms?

I just really need to know how to solve these. Thanks.

- Chemistry=MOLES! -
**drwls**, Tuesday, January 1, 2008 at 1:38pm
<<What is the mass in grams of 0.99x10^49 Sodium Chloride Molecules?>>

First find out how many moles that is by dividing by Avogadro's number, 6.02*10^23 molecules/mole. You get 1.64*10^25 moles. Then multiply that result by 58.5 gm/mole, the molar mass of NaCl.

You will get a very large number, comparable to the mass of the Earth. Are you sure you copied the problem correctly?

<<How many moles of Cu are in 9.61 grams?>>

Divide by the atomic mass of Cu, 63.5 g/mole

<<How many moles are in 5.94x10^45 Ne atoms?>>

Multiply that by the atomic mass of Neon, which it would be a good idea to look up, so that you get some practice doing this sort of thing.

- Chemistry=MOLES! -
**DrBob222**, Tuesday, January 1, 2008 at 1:40pm
The two pertinent pieces of information are here.

mols = grams/molar mass

There are 6.02 x 10^23 anythings in a mol; therefore,

mols = # atoms/6.02 x 10^23

or

mols = # molecules/6.02 x 10^23

Let me know if this doesn't help but explain in detail what the problem is.

- Chemistry=MOLES! -
**Damon**, Tuesday, January 1, 2008 at 1:42pm
Well, you know that twelve of anything is a dozen of them.

In exactly the same way, 6.022*10^23 of atoms or molecules is a mole of them.

## Answer This Question

## Related Questions

- CHEM MOLES !@@! - Mole Calculation Worksheet 1) How many moles are in 15 grams ...
- chemistry - 1.How many atoms are in a sample of copper with a mass of 18.46 ...
- chemistry - 1.How many atoms are in a sample of copper with a mass of 18.46 ...
- chem1 WORD PROBLEM!! - 6. how many grams are in 4 moles of Be (OH)3? 7.How many ...
- Chemistry - 1)The chemical formula for aspirin is C9H8O4. What is the mass of 0....
- chemistry Emergency TEST - 1.How many moles of sodium oxide are produced when3.9...
- CHEM !(MOLE) PLZ HELP! - 1.How many grams are in one mole silicon? 2. how many ...
- chemistry - how many grams of sodium carbonate are needed to prepare 0.250 L of ...
- Honors Chemistry (stoichiometry) - Can someone check and make sure I'm doing ...
- chemistry - 8.What is the mass of 4.56 moles of sulfur dioxide? 9.What is the ...

More Related Questions