Chemistry Week

25

Please get out your Classwork and a

calculator!

March 6, 2013

AGENDA:1 – Agenda/ Bell Ringer 2 – Review HW3 – CN: Gram to Gram

Stoichiometry4 – Work Time

Today’s Goal:Students will be able to

convert complete 3-step stoichiometry conversions between grams and grams.

Homework1. Gram to Gram

Stoichiometry2. Friday is the Last Day

to make up last week’s quiz.

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 HW3 – CN: Gram to Gram

Stoichiometry4 – Work Time

Today’s Goal:Students will be able to

convert complete 3-step stoichiometry conversions between grams and grams.

Homework1. Gram to Gram

Stoichiometry2. Friday is the Last Day

to make up last week’s quiz.

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

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 Bx b

a

Obj: SWBAT complete 3-step stoichiometry conversions between grams and grams.

Date: 3/6/2013

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?1. 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 MgOGrams A Mole A Mole B Gram

BHow many grams of MgO would you form

from 25 gram of Mg?25 g Mg x 1 mol Mg

24.3 g Mg x

2 mol Mg2 mol MgOx =

1 mol MgO40.3 g MgO

25 x 1 x 2 x 40.3 g MgO 24.3 x 2 x 1

= 201548.6

= 41.5 g MgO

Set-Up Help

Balanced Chem Eq: aA bB1. Calculate the molar masses of both

compounds in the problem2. Convert: remember Given and WantGiven(g) x1 mol Given x mol Want x Mol.mass Want =

Mol.mass Given mol Given 1 mol Want3. Multiply everything in numerator. 4. Multiply everything in the denominator5. 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 BGram A x 1Mole A x b Mole B = Mole B

Molar Mass A a mol A