limiting and excess reagent in chemical reaction

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1. Limiting and Excess reactant By:Monica Filomena M. Taberdo

2. Limiting reactant The reactant that is completely used in an reaction. It determines the amount of product form. Excess reactant It is not completely consumed in a reaction .

3. e.g. I n a dance party when a slow song is played, the students normally form pairs to dance. If they are 8boys and 20girls , only 8 girls will be able to pair up with the boys to dance.

4. e.g. 2 Al +3 Cl2 = 2 AlCl3 If the ratio of Al and Cl2 is 2:3 Mole available : 3 mole Al, 3 mole Cl2 Mole consumed : 2 mole Al, 3mole Cl2 Mole reactants not reacted : 1 mole Al, 0 mole Cl2

5. In an experiment, 5.00 g aluminum is heated with 25.00 g sulfur to form aluminum sulfide. Find the ff : Mass Al2S3 Mass excess reactant.

6. Step 1: find the limiting reactant Step 2: use the value of limiting reactant in finding the mass of Al2S3