Stoichiometry

Warm-Up

Example of stoich problem Magnesium metal burns in the air Mg (s) + O 2(g) MgO (s) 2 Mg (s) + O 2(g) 2 MgO (s) 3g? g

Example of stoich problem 2 Mg (s) + O 2(g) 2 MgO (s) 3 g? g 3 g 1 mol 24.3 g 24.3 g/mol 40.3 g/mol mol 1 mol 40.3 g

Example of stoich problem 2 Mg (s) + O 2(g) 2 MgO (s) 3 g 4.96 g 3 g 1 mol 24.3 g 24.3 g/mol 40.3 g/mol mol 1 mol 40.3 g

Percent Yield 2 Mg (s) + O 2(g) 2 MgO (s) 3 g 4.96 g (theoretical) 24.3 g/mol 40.3 g/mol mol 3.72 g (actual) 3.72/4.96 x 100% = 75%

Questions that can be asked 2 Mg (s) + O 2(g) 2 MgO (s) 3 g? g 24.3 g/mol 40.3 g/mol mol

Questions that can be asked 2 Mg (s) + O 2(g) 2 MgO (s) 3 g? g 24.3 g/mol 32.0 g/mol mol How much oxygen is used in this reaction?

Questions that can be asked 2 Mg (s) + O 2(g) 2 MgO (s) 3 g? g 24.3 g/mol 32.0 g/mol mol 3 g Mg 1 mol Mg 24.3 g Mg 2 mol Mg 1 mol O 2 = 1.97 g O 2 1 mol O g O 2 mole ratio