Download - Chemistry Week 24
Chemistry Week
24
Please get out your Classwork and
calculator!
Feb 27th, 2013
AGENDA:1 – Agenda Bell Ringer2 – Notes: Mole
Conversion: 2 step conversions
3 – Work Time
Today’s Goal:Students will be able to
convert between moles, grams and particles.
Homework1. Mole Conversions
Wkst 2 – due tomorrow! (change to classwork assignment)
2. Work from Week 23 due by Friday
Wednesday, February 27
Objective: Students will be able to convert between
moles, grams and particles.
Bell Ringer: How many grams are in 3.75 moles
of H2SO4?
2 MINUTES REMAINING…
Wednesday, February 27
Objective: Students will be able to convert between
moles, grams and particles.
Bell Ringer: How many grams are in 3.75 moles
of H2SO4?
1 MINUTES REMAINING…
Wednesday, February 27
Objective: Students will be able to convert between
moles, grams and particles.
Bell Ringer: How many grams are in 3.75 moles
of H2SO4?
30 seconds Remaining…
Wednesday, February 27
Objective: Students will be able to convert between
moles, grams and particles.
Bell Ringer: How many grams are in 3.75 moles
of H2SO4?
10 seconds Remaining…
BELL-RINGER TIME IS
UP!
Feb 27th, 2013
AGENDA:1 – Agenda Bell Ringer2 – Notes: Mole
Conversion: 2 step conversions
3 – Work Time
Today’s Goal:Students will be able to
convert between moles, grams and particles.
Homework1. Mole Conversions
Wkst 2 – due tomorrow! (change to classwork assignment)
2. Work from Week 23 due by Friday
Wednesday, February 27
Objective: Students will be able to convert from
moles to grams and moles to particles.
Bell Ringer: How many grams are in 3.75 moles
of H2SO4?
Molar mass of H2SO4 = 98.1 g/mol.3.75 moles x 98.1 grams =
1 mole
3.75 x 98.1 g
= 367.9 g
Mole Conversions
Topic: Mole Conversions Part 2 Date: 2/26/2013 Yesterday mole to gram conversions
Example: If you have an 8.0 mole sample of NaCl, how many grams do you have?
1. NaCl =Na =Cl = 58.44 g
1 mol
1x+______1x
2. 8.0 mole NaCl x 58.44 g
1 mol
= 467.52 g NaCl
22.9935.45
= 22.99= 35.45
What if you were given a 200 g sample of NaCl, and you wanted to convert to moles?
Molar Mass of NaCl =
200 g
Gram to Mole
58.44 g
1 mole
x 1 mole =
58.44 g
200 mole =58.44
3.42 mol NaCl
mole gram
multiplication
gram mole
division
1 mole
58.44 g
=
Gram to Mole (cont)
Example: If you have a 150 g sample of AlPO4, how
many moles do you have?
1. AlPO4 =Al =P =O = 121 g
mol
1 x
+1 x
2. 150 g x 1 mol 121 g
= 1.24 mol AlPO4
2631
= 26= 31
4 x 16 = 64
Mole to Particle Conversion Conversion
YESTERDAY Imagine if you want to know HOW
MANY atoms are in 1.5 moles of silver metal…
1.5 moleX 6.02 x
1023 1 mole
= 9.03 x 1023 atoms
What if you were given a 2.00 x 1026 particles sample of NaCl, and you wanted to convert to moles?
2.00x 1026 particles
Particle to Mole
x 1 mole =
6.02 x 1023 part
2.00 x 1026 mole 6.02 x 1023
3.32 x 102 mol NaCl
mole particles
multiplication
particles mole
division
Problem Solving Decision Tree
Read the problem
If moles and grams
Calculate Molar Mass
If moles grams
If moles and particles
Multiply by molar mass
If grams moles
Divide by molar mass
If moles particles
Multiply by6.02 x 1023
If particles moles
Divide by6.02 x 1023
Mole to Gram Conversion
Imagine if you want to measure out a 1.5 mole sample of silver metal…? Could you count out 1.5 moles? But you can use molar mass to convert
moles to grams, and you can measure grams.
Molar Mass of Silver =
1.5 mole
107.9 g Ag
1 mole Ag
... NO!
x 107.9 g = 1 mole
1.5 x 107.9 g =
161.8 g Ag
Practice Problems
If you had a 7.5 mole sample of H2O, how many grams would you have?1. Determine the molar mass.2. Convert! (Watch units!)
1. H2O =2xH =O =
18.0 g 1 mol
(2 x 1.0)+ 16.0
2. 7.5 mole H2O x 18.0 g
1 mol= 7.5 x 18.0 g H2O
= 135.0 g H2O
What if you were given a 200 g sample of NaCl, and you wanted to convert to moles?
Molar Mass of NaCl =
200 g
Gram to Mole
58.5 g
1 molex 1 mole
=
58.5 g
200 mole =58.5
3.4 mol NaCl
mole gram
multiplication
gram mole
division
1 mole
58.5 g
=
What if you were given a 2.00 x 1026 particles sample of NaCl, and you wanted to convert to moles?
2.00x 1026 particles
Particle to Mole
x 1 mole =
6.02 x 1023 part
2.00 x 1026 mole 6.02 x 1023
= 3.32 x 102 mol NaCl
mole particles
multiplication
particles mole
division