The Mole Q: how long would it take to spend a mole of $1 coins if they were being spent at a rate of 1 billion per second?
Molar mass The mass of one mole is called “molar mass” E.g. 1 mol Li = 6.94 g Li This is expressed as 6.94 g/mol What are the following molar masses? SSO 2 Cu 3 (BO 3 ) g/mol g/mol g/mol Calculate molar masses (to 2 decimal places) CaCl 2 (NH 4 ) 2 CO 3 O 2 Pb 3 (PO 4 ) 2 C 6 H 12 O 6 Cux 3 = x 3= Bx 2 = x 2= Ox 6 = x 6=
Molar mass The mass of one mole is called “molar mass” E.g. 1 mol Li = 6.94 g Li This is expressed as 6.94 g/mol What are the following molar masses? SSO 2 Cu 3 (BO 3 ) g/mol64.06 g/mol g/mol Calculate molar masses (to 2 decimal places) CaCl 2 (NH 4 ) 2 CO 3 O 2 Pb 3 (PO 4 ) 2 C 6 H 12 O g/mol (Ca x 1, Cl x 2) g/mol (N x 2, H x 8, C x 1, O x 3) g/mol (O x 2) g/mol (Pb x 3, P x 2, O x 8) g/mol (C x 6, H x 12, O x 6)
Converting between grams and moles If we are given the # of grams of a compound we can determine the # of moles, & vise-versa In order to convert from one to the other you must first calculate molar mass g = mol x g/mol mol = g g/mol This can be represented in an “ equation triangle ” g molg/mol g= g/mol x mol0.25HCl 53.15H 2 SO NaCl 1.27Cu Equationmol (n)gg/molFormula mol= g g/mol g= g/mol x mol mol= g g/mol