Classwork and a calculator! Chemistry Week 25 Please get out your Classwork and a calculator!

March 6, 2013 AGENDA: 1 – Agenda/ Bell Ringer 2 – Review HW Today’s Goal: Students will be able to convert complete 3-step stoichiometry conversions between grams and grams. Homework Gram to Gram Stoichiometry Friday is the Last Day to make up last week’s quiz. AGENDA: 1 – Agenda/ Bell Ringer 2 – Review HW 3 – CN: Gram to Gram Stoichiometry 4 – Work Time

Wednesday, March 6th Objective: Students will be able to convert complete 2-step stoichiometry conversions between grams and grams. Bell Ringer: 2 C4H10 + 13 O2  8 CO2 + 10 H2O Set-up the units for converting moles of O2 to grams of CO2. Moles O2 x ________ x _________ = grams CO2

March 6, 2013 AGENDA: 1 – Agenda/ Bell Ringer 2 – Review HW Today’s Goal: Students will be able to convert complete 3-step stoichiometry conversions between grams and grams. Homework Gram to Gram Stoichiometry Friday is the Last Day to make up last week’s quiz. AGENDA: 1 – Agenda/ Bell Ringer 2 – Review HW 3 – CN: Gram to Gram Stoichiometry 4 – Work Time

Wednesday, March 6th Objective: Students will be able to convert complete 2-step stoichiometry conversions between grams and grams. Bell Ringer: 2 C4H10 + 13 O2  8 CO2 + 10 H2O Set-up the units for converting moles of O2 to grams of CO2. Moles O2 x moles CO2 x molar mass CO2= gCO2 moles O2 1 mol CO2

Obj: SWBAT complete 3-step stoichiometry conversions between grams and grams. Date: 3/6/2013 Balanced Chemical Equation: a A  b B Coefficients = # moles of each compound Grams Moles Moles Grams A A B B ÷ Molar Mass of A x Molar Mass of B x b a

2 Mg + 1 O2  2 MgO Grams A  Mole A  Mole B  Gram B How many grams of MgO would you form from 25 grams of Mg? Calculate Molar Mass for both compounds in the problem. 1. Molar Mass Mg = 24.3 O = + 16 40.3 g 1mol 2. Molar Mass Mg = 24.3 24.3 g 1mol

Practice Problem: Gram A  Mole A  Mole B  Gram B 2 Mg + 1 O2  2 MgO Grams A  Mole A  Mole B  Gram B How many grams of MgO would you form from 25 gram of Mg? 1 mol Mg 2 mol MgO 40.3 g MgO 25 g Mg x x x = 2 mol Mg 24.3 g Mg 1 mol MgO 25 x 1 x 2 x 40.3 g MgO 24.3 x 2 x 1 2015 48.6 = = 41.5 g MgO

Set-Up Help Balanced Chem Eq: aA  bB Calculate the molar masses of both compounds in the problem Convert: remember Given and Want Given(g) x1 mol Given x mol Want x Mol.mass Want = Mol.mass Given mol Given 1 mol Want Multiply everything in numerator. Multiply everything in the denominator Divide Numerator by Denominator.

Set-Up Help Balanced Chem Eq: aA  bB Mole A  Mole B  Gram B: Mole A x b Mole B x Molar Mass B = Gram B a Mole A 1 mol B Gram A  Mole A  Mole B Gram A x 1Mole A x b Mole B = Mole B Molar Mass A a mol A