[shannon]

Hi everyone! My name is Shannon and I am new to this site. I took Intro. Chem. over a year ago, so now that I am starting General Chemistry, I am beginning to realize how much information I lost over that year. 

Currently we are working on Hydrate Formulas, and I have been stuck on one particular problem for a while. The problem states:

Na₂CO₃ . 10H₂O is known as washing soda. It is used as soap extender. If 50.00 grams of washing soda is used, what weight is actually Na₂CO₃?

I know that "10" is the moles of water divided by the moles of anhydrous salt, but I don't know where to go from there. If someone could please explain to me how to go about solving this problem, I'd really appreciate it! 

[Dan]

Well, what is the relative formula mass of Na₂CO₃.10H₂O?

How many moles of formula units in 50g?
How many moles of Na₂CO₃ in 50g?
What mass of Na₂CO₃ in 50g of the hydrate?

P.S. Colour is fine, but could you use standard text size please? I have done this in your post above. Cheers.