Objectives:
Objectives Define molar mass. Find the molar mass of an element using the periodic table. Calculate the molar mass of a compound.
Molar mass:
Molar mass 1 mole represents a specific number of particles 1 mole has a certain mass -> Measure in grams on a balance * 1 dozen apples have a different mass than 1 dozen paper clips 1 mole of atoms will have a particular mass, but it will depend on the element 1 mole of carbon atom has a mass of 12.01 grams
Molar mass of elements:
Molar mass of elements Average atomic mass is found on the periodic table for each element Average atomic mass is measured in ( amu ) -> mass of an atom Molar mass is measured in grams/mol -> Mass of a mole of a particles
Molar mass of diatomic elements:
Molar mass of diatomic elements Since there are two atoms in each molecule, the molar mass is twice the average atomic mass Molar mass of O2 - 2 atoms 0 per molecule - 1 mole 0 atom has a molar mass of 16.00 g/mol - 1 mole O2 molecules has a molar mass of 32.00 g/mol
Mass of polyatomic elements:
Mass of polyatomic elements Example: O3 Average atomic mass of 0=16.00 amu Molar mass of 0=16.00 g/mol Molar mass of O3 3 x 16.00 g/mol= 48.00 g/mol
Calculating Molar Mass :
Calculating Molar Mass 1.) Write the formula. 2.) List the types of atoms. 3.) Count each type of atom, using subscripts, and write down the count. 4.) Multiply the count by the average atomic mass of the element. 5.) Total all the masses.
Sample Problem:
Sample Problem Ammonium Sulfate (NH4)2SO4 N 2 x 14.01= 28.02 H 8 x 1.01= 8.08 S 1 x 32.07= 32.07 O 4 x 16.00= 64.00
Thank you so much !!!:
Thank you so much !!! Prepared by : Beverly Ibañez Julia Ann Entuciasmo Abegail Rebay