Chapter 9

Stoichiometry

Pancake Recipe

• 1 cup flour

• 2 eggs

• ½ cup water

• ¼ tsp baking powder

• Makes 5 pancakes

• We can write this recipe as an equation.

1 cup flour + 2 eggs + ½ cup water + ¼ tsp. baking powder → 5 pancakes

• If I have a 3 cups of flour how many pancakes can I make?

1 cup flour + 2 eggs + ½ cup water + ¼ tsp. baking powder → 5 pancakes

• How many cups of water will I need if I have 1 dozen eggs?

1 cup flour + 2 eggs + ½ cup water + ¼ tsp. baking powder → 5 pancakes

• How many tsp. of baking powder will I need to make 13 pancakes?

Chemical Equations are Recipes for Chemicals

5C + 2SO2 → CS2 + 4CO

• How do we interpret this equation?

5 mol C + 2 mol SO2 → 1 mol CS2 + 4 mol CO

IT TAKESIT TAKES MOLESMOLES TOTO MOVEMOVE

5C + 2SO2 → CS2 + 4CO

• 7.42 mol C will produce how many mol CO?

IT TAKESIT TAKES MOLESMOLES TOTO MOVEMOVE

5C + 2SO2 → CS2 + 4CO

• 3 mol CS2 require how many mol C?

IT TAKESIT TAKES MOLESMOLES TOTO MOVEMOVE

C6H12O6 + 6O2 → 6CO2 + 6H2O

• 3.60 mol C6H12O6 produce how many mol CO2?

IT TAKESIT TAKES MOLESMOLES TOTO MOVEMOVE

2KClO3 → 2KCl + 3O2

• 5.42 mol KClO3 will produce how many mol O2?

IT TAKESIT TAKES MOLESMOLES TOTO MOVEMOVE