1.  Predict the products and write a balanced equation for the following: BaCl 2 + MgSO 4 

3.  Greek for “measuring elements”  The calculations of quantities in chemical reactions based on a balanced equation.  We can interpret balanced chemical equations several ways.

4.  Two molecules of hydrogen and one molecule of oxygen form two molecules of water.  2 dozen molecules of hydrogen and one dozen molecules of oxygen form two dozen molecules of water.  Two moles of hydrogen and one mole of oxygen form two moles of water  This does not work with mass!!!!

5.  2 Al 2 O 3  Al + 3O 2  every time we use 2 moles of Al 2 O 3 we make 3 moles of O 2  This is called a mole ratio 2 moles Al 2 O 3 3 mole O 2 or 2 moles Al 2 O 3 3 mole O 2

6.  How many moles of O 2 are produced when 3.34 moles of Al 2 O 3 decompose? 3.34 mol Al 2 O 3 2 mol Al 2 O 3 3 mol O 2 =5.01 moles O 2 2 Al 2 O 3  Al + 3O 2

7. 2C 2 H 2 + 5 O 2  4CO 2 + 2 H 2 O  If 3.84 moles of C 2 H 2 are burned, how many moles of O 2 are needed?  How many moles of C 2 H 2 are needed to produce 8.95 mole of H 2 O?

8.  If 3.6 mol of Fe are added to a solution of Copper (II) Sulfate, how many grams solid copper would form?  2Fe + 3CuSO 4  Fe 2 (SO 4 ) 3 + 3Cu 3.6 mol Fe 3 mol Cu 2mol Fe = 2.4 mol Cu 5.4 mol Fe 63.55g Cu 1mol Fe = 343.17g Cu

9. To make silicon for computer chips they use this reaction SiCl 4 + 2Mg  2MgCl 2 + Si  How many grams of Mg are needed to make 9.3mol of Si?  How many grams of SiCl 4 are needed to make 9.3mol of Si?

10.  When methane gas is heated with oxygen gas, the two will combust and form carbon dioxide and water CH 4 + 2O 2  CO 2 + 2H 2 O  How many moles of H 2 O will be formed when 28.0 g of methane combusts? 28.0g CH 4 16.05 g CH 4 1 mol CH 4 =1.74 mol CH 4 1 mol CH 4 2 mol H 2 O =3.48 mol H 2 O

11. The first step in the industrial manufacture of nitric acid is the catalytic oxidation of ammonia. 4NH 3 (g) + 5O 2 (g) → 4NO(g) + 6H 2 O(g) How many moles of NO can be formed from 825g NH 3 ? How many moles of H 2 O are formed from 825 g NH 3 ?

12.  Use the following equation to answer the questions: 4NH 3 + 3O 2  2N 2 + 6H 2 O 1. How many moles of N 2 are formed from 4 moles of NH 3 ? 2. How many moles of H 2 O will be produced when 5 moles of N 2 are formed? 3. How many moles of O 2 are required to react with 25g of NH 3 ? 4. How many moles of N 2 can be formed is 100g of O 2 is mixed with NH 3 ? 5. How many grams of H 2 O are produced if 3.7mol of O 2 is mixed with NH 3 ? 6. How many grams of NH 3 are required to produce 5mol of O 2 ?