Aim: How can the amount of product be predicted?

Do Now: 1.Take out a calculator and reference tables.2.Label the following reactions as synthesis,

decomposition, single replacement or double replacement.

Zn + 2HCl ZnCl2 + H2

2NaClO3 2NaCl + 3O2

P4 + Cl2 PCl3

2HNO3 + Mg(OH)2 Mg(NO3)2 + 2H2O

*** Reminder ***• What does the law of conservation of matter say? • The number of atoms on each side of a chemical reaction

must be equal.• How can we use this information? We can use this

information to determine the amount of product created or the amount of reactants used.

• Problems solved with this information include: 1. Mole-mole problems 2. Mole-mass problems3. Mass-mass problems4. Mass – volume problems5. Volume – volume problems

Mole – Mole Problems• Answers how many moles of one element or

compound react with a given number of moles of another compound.

• Example: How many moles of Ca are needed to react completely with 6 moles of H2O in the following reaction:

Ca + 2H2O Ca(OH)2 + H2

Practice Problems1. Given the reaction: 2CO2 + O2 2CO2 What is the

minimum number of moles of O2 required to produce 1mole of CO2?

2. Given the reaction: 2KClO3 2KCl + 3O2 What is the total number of moles of KClO3 needed to produce 6 moles of O2?

3. Given the reaction: 2NaOH + H2SO4 Na2SO4 + 2H2O What is the total number of moles of NaOH needed to react completely with 2 moles of H2SO4?

Mole – Mass Problems• Answer how many grams of reactants or products

are used/created within a specific formula.• Example: If 103.0g of KClO3 are decomposed to

form 62.7g of KCl and O2 gas according to the equation 2KClO3 2KCl + 3O2 how many grams of oxygen are formed?

Practice Problems1. What mass of carbon dioxide will be produced if

144g of carbon react with 384g of oxygen gas according to the equation C + O2 CO2?

2. How many grams of silver nitrate are needed to react with 156.2g of sodium sulfide to produce 595.8g of silver sulfide and 340.0g of sodium nitrate according to the equation 2AgNO3 + Na2S Ag2S + 2NaNO3?

Mass – Mass Problems• Give you the grams of one element or compound

and ask you to find the grams of another element or compound using the equation given.

• Example: How many grams of calcium are needed to react completely with 108 grams of H2O in the equation

Ca + 2H2O Ca(OH)2 + H2

Mass – Volume Problems• Deals with one element or compound in grams and

one element or compound in millilters or liters. • Example: How many liters of N2 will react with 36g

of H2 at STP given the equation N2 + 3H2 2NH3

Volume – Volume Problems• Gives you liters or milliliters of one element or

compound and asks you to find liters or milliliters of the other compound or element. (Use the same unit while solving).

• Example: What is the total number of liters of carbon dioxide formed by the complete combustion of 28 liters of C2H6 using the equation

2C2H6 + 7O2 4CO2 + 6H2O

Activity/Homework

• Complete the regents questions on the back of today’s notes.