Quoting Post Archived Topic: It will not be bumped to the top of the forum. Topic Chemistry Help! Membername   Not a member? Sign Up Free (takes 20 seconds) Password   Forgotten your password? Post Font: Verdana Arial Black Georgia Comic Sans Impact   Size: Tiny Normal Big Huge   Color: Default Dark Red Red Orange Brown Green Olive Cyan Blue Dark Blue Indigo Black [ Check Spelling ] [ Post Preview ] [ LiveTags ] Quote: from [m]Amazingness99[/m] at 5:28 pm on Jan. 5, 2009[quote]Calculate the molar mass of Al2(PO4)3 first. Then, divide 250 by the number you got and you should get the moles of that substance.[/quote] FAQ Keyword Search: Post Options Favorites Manager Notify me of new replies to this topic by email Notify me of new replies to this topic by private message Original Post morgan82 Posted at 5:27 pm on Jan. 5, 2009 I have 250 grams of Al2(PO4)3 How many moles of Al are there?

Replies Just Waiting Here Posted at 5:38 pm on Jan. 5, 2009 You need to calculate the molar mass.  You do this by using the weights that you get off of a periodic table. You have Al2(PO4)3, which means you have 2 aluminum, 3 phosphorus, and 12 oxygen. Add up all the weights together to get your molar mass of this compound. Since you have 250 grams, and molar mass is in grams per mole, you need to divide 250 by the number you just calculated.  This will give you the number of moles. mynoselikesopiates Posted at 5:32 pm on Jan. 5, 2009 cook up some meth Heart92 Posted at 5:29 pm on Jan. 5, 2009 Do you have more questions? I can help you out with the others. Amazingness99 Posted at 5:28 pm on Jan. 5, 2009 Calculate the molar mass of Al2(PO4)3 first. Then, divide 250 by the number you got and you should get the moles of that substance. All 4 previous replies displayed.