Living By Chemistry SECOND EDITION Unit 4 TOXINS

Living By Chemistry SECOND EDITION Unit 4: TOXINS Stoichiometry, Solution Chemistry, and Acids and Bases

Lesson 92: Mole Tunnel Stoichiometry

Chem. Catalyst This reaction produces the main substance found in human bones (calcium phosphate): 3 Ca. Cl 2(aq) + 2 Na 3 PO 4(aq) Ca 3(PO 4)2(s) + 6 Na. Cl(aq) Calcium Sodium chloride phosphate chloride 1. How many moles of calcium phosphate can you make using 6 moles of calcium chloride, Ca. Cl 2 2. How many moles of calcium phosphate can you make using 111 g of Ca. Cl 2?

Key Question How do you convert between grams and moles to determine the mass of product?

You will be able to: • complete stoichiometric calculations for a variety of chemical reactions.

Prepare for the Classwork Work in pairs. Stoichiometry: the quantitative relationship between reactants and products in a chemical reaction.

Discussion Notes When working stoichiometric problems, grams must be converted to moles and then moles must be converted back to grams.

Wrap Up How do you convert between grams and moles to determine the mass of product? • In order to calculate the mass of reactant needed to make a certain mass of product, it is necessary to convert mass to moles and then convert moles back to mass. • Mole ratios assist in converting back and forth between moles of reactant and moles of product.

Check-In Consider this reaction: Mg(s) + 2 HCl(aq) Mg. Cl 2(aq) + H 2(g) How many grams of magnesium, Mg, do you need to produce 190 g of magnesium chloride, Mg. Cl 2?