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Title: How do I determine the number of moles of compound?? Post by: ilibee on Feb 15, 2013 Can you please explain how to do this??
Determine the number of moles of compound in each of the following samples; a. 4.50g H2O b. 129.68g Fe3(PO4)2 Title: How do I determine the number of moles of compound?? Post by: tosia on Feb 15, 2013 One mole is defined as the amount of a substance so that its mass is equal to its formula weight:
Moles = mass / FW. So simply determine the formula weights for each compound (from the periodic table), and divide the mass in the sample by the formula weight. Title: How do I determine the number of moles of compound?? Post by: rivertube on Feb 15, 2013 Atomic mass is found from the Periodic Table of Elements.
a...Mol. mass of H2O = 18g/mole. (H.1x2) + (O.16x 1) Moles = Mass/Mol.mass = 4.5g/18g/mol. = 0.25 moles H2O. b...Mol. mass of Fe3(PO4)2.. = (Fe.56 x 3) + (P.31 x 2) + (O.16 x 8) = 168 + 62 + 128 = 358g/mol. 129.68g/358/g/mol. = 0.362 moles Fe3(PO4)2 Title: How do I determine the number of moles of compound?? Post by: tony12 on Feb 15, 2013 General formula: m=nM where m is the mass, n is the no. of mol, and M is th molar mass.
a. n(H2O)= m/M = 4.5/18=..................... b. n(Fe3(PO4)2)= 129.68/ the molar mass. u get the molar masses from the periodic table. How?? eg: M (H2O)= 2xM(H) + M(O) = 2(1)+16= 18 g/mol Title: How do I determine the number of moles of compound?? Post by: Toshamarrie on Feb 15, 2013 a...Mol. mass of H2O = 18g/mole.
Moles = Mass/Mol.mass = 4.5g/18g/mol. = 0.25 moles H2O. b...Mol. mass of Fe3(PO4)2.. = (56 x 3) + (31 x 2) + (16 x 8) = 168 + 62 + 128 = 358g/mol. 129.68g/358/g/mol. = 0.362 moles Fe3(PO4)2 please chose me for best i really need it |