C: 2 Nov. 2010

C: 2 Nov. 2010

Objective: SWBAT show what you know about the language of chemistry on a test, and convert between atoms/molecules and moles of an element.

Do now: What type of question are you most confident about?

What type of question are you least confident about?

C: Agenda

I. Do nowII. Test! Language of ChemistryIII. The Mole – notesIV. Converting between moles and number of

atoms and moles and massV. Practice ProblemsHomework: Week 9 Homework: #1-26: Weds.Bring your calculator EVERY day!! Calculator check = 10 point quiz tomorrow!

A: 2 November 2010

Take Out Homework: Week 8 Test Review

Objective: SWBAT show what you know about the language of chemistry on a test.

Do now (in your notebook): What type of question are you most confident about?

What type of question are you least confident about?

A: Agenda

I. Do nowII. Test! Language of ChemistryHomework: Bring a calculator EVERY

day!Calculator check = 10 point quiz

tomorrow!

Test

The periodic table is on the last page. You can rip it off if you’d like.

When you are finished, turn your test over on your desk.

Work on something silently Missed work for chem, work for

another class, read a book, etc… Remain silent, even if you are

finished!

A: 3 Nov. 2010

Take out your calculator! Objective: SWBAT convert between

atoms/molecules and moles and mass of an element.

Do now: (In your notebook) We buy eggs by the dozen, and shoes by the pair. Name at least two other things that you buy in multiples (that is, more than one at a time).

Agenda

I. Do now, calculator checkII. Notes on the Mole, converting between

moles and number of atoms/particlesIII. Practice ProblemsIV. Converting between moles and mass of

elementsV. Practice ProblemsHomework: Week 9 Homework #1-34

odds: Thurs.

Announcement

I’m going to underline the things you should write down.

If it’s not underlined, don’t write it down.

New Unit: Stoichiometry The calculation of the amounts of matter

used in a chemical reaction and produced by a chemical reaction.

H2(g) + O2(g) H2O(g) If 5 grams of hydrogen is reacted with 5

grams of oxygen, how many grams of water will be formed? Will any hydrogen or oxygen be left over? How much?

The Mole

Atoms are so tiny; how do we quantify their masses?

We communicate the mass of atoms in terms of really, really huge groups of atoms.

6.02x1023 atoms, to be exact!

The Mole

Mole: The scientific unit for amount of substance

=6.02x1023 atoms or molecules =Avogadro’s Number

How big is a mole?

Enough soft drink cans to cover the surface of the earth to a depth of over 200 miles.

If you had Avogadro's number of unpopped popcorn kernels, and spread them across the United States of America, the country would be covered in popcorn to a depth of over 9 miles.

If we were able to count atoms at the rate of 10 million per second, it would take about 2 billion years to count the atoms in one mole.

Really? How big?

1 mole of pennies could be distributed to all the currently-living people of the world so that they could spend a million dollars per hour every hour (day and night) for the rest of their lives.

1 mole of blood cells would be more than the total number of blood cells found in every human on earth.

Amadeo Avogadro

Italian Born: 1776 Studied physics

and math Taught high school,

then college

Converting between moles and atoms/molecules

Two possible conversion fractions

moleculesatomsx

mole

/1002.6

123 mole

moleculesatomsx

1

/1002.6 23

Example 1

How many moles are equal to 3.50x1023 atoms of silver?

Example 2

How many moles are equal to 1.25x1024 molecules of sodium bromide?

Example 3

How many atoms are there in 1.50 moles of sulfur?

Example 4

How many molecules are there in 10.55 moles of water?

1. How many moles of silver are equal to 3.01 x 1023 atoms of silver?

2. How many moles of water are equal to 2500 molecules of water?

3. How many atoms of carbon are in 3.2 moles of carbon?

4. How many molecules of calcium chloride are in 1.0 mole of calcium chloride?

C: 8 November 2010

Take Out Homework: Week 9 #1-18 and your calculator!

Objective: SWBAT convert between atoms, moles and mass of elements.

Do now: Choose and write the correct fraction to convert if… a. The problem gives you atoms and asks

for moles. b. The problem gives you moles and asks

for atoms.

Agenda

I. Do now, calculator checkII. Homework answersIII. Convert between moles and mass

of elementsIV. Convert between atoms, moles,

and mass of elementsHomework: Week 9 Homework #19-

34: Weds.

Converting between moles and mass of elements Two possible conversion fractions:

)(_

1

gmassatomic

mole

mole

gmassatomic

1

)(_

Example 1

Calculate the mass in grams of 3.50 moles of hydrogen.

Example 2

Calculate the number of moles equal to 10.0 grams of silicon.

1. What is the mass in grams of 3.50 mol of copper?

2. What is the mass in grams of 2.25 mol of iron?

3. How many moles of aluminum are equal to 11.9 grams of Aluminum?

4. How many moles of calcium are equal to 5.00 grams of calcium?

A: 4 Nov. 2010

Take Out Homework: Week 9 Homework #1-26 odds

Objective: SWBAT convert from mass to moles to atoms and calculate molar mass.

Do now: a. Calculate the number of moles equal to

5.00x1025 atoms of gold.b. Calculate the mass of 5.00 moles of gold.

Agenda

I. Do nowII. Homework checkIII. Mass to moles to atoms examples

and problemsIV. Calculating molar mass examples

and problemsHomework: Week 9 Homework #27-

38: Mon.

Mass to moles to atoms

Ex 1: Calculate the mass of 8.00x1023 atoms of gold.

Ex 2: Calculate the number of atoms in 5.00 grams of bromine.

1. Calculate the mass of 3.01x1025 atoms of copper.

2. Calculate the number of atoms in 10.0 grams of lithium.

3. Calculate the mass of 5000. atoms of zinc.

4. Calculate the number of atoms in 1.000 grams of beryllium.

C: Homework

Week 9 Homework #19-34: Weds. Bring calculator every day!

A: 8 Nov. 2010

Take Out Homework: Week 9 #27-34

Objective: SWBAT convert between mass, moles and number of atoms of an element

Do now: (In your notebook) Calculate the mass of 500. atoms of cobalt.

Agenda

I. Do nowII. Homework checkIII. Using the electronic balanceIV. Mass to moles to atoms stationsHomework: Fix Week 9 #1-34Hand in missing work!

Using an electronic balance

Press “on” If the display does not read “0.00,”

press “zero.” Gently place the item to be massed

on the metal plate. Record the mass with TWO decimal

places (ex: 4.50 g).

Using an electronic balance

Treat these balances with extreme care! They cost about $250 each.

Never place anything directly on the metal plate, including your fingers!

Press buttons gently. Never push or pull on any part of the

balance. If a problem occurs, let me know

immediately.

Mass to moles to atoms lab

On the front: Find the mass of the sample.

Subtract the mass of the container (given on the card).

Convert to moles Convert to number of atoms

On the back: Copy down the number of atoms

(from the card) Convert to moles Convert to mass Check your answer by massing the

sample on the balance.

Homework

Week 9 Homework: Check #1-34 Mass, moles, atoms lab: Finish,

check for units and element symbols Due tomorrow

Late work due by 3:15 today!!

Do your best!

Work carefully and quickly!! Low grades result from sloppy work,

not showing work, not writing down units and wasting time during labs.

This is a 1st quarter grade! 5 min. per station.

Homework

Check and fix Week 9 Homework #1-34

C: Homework

Week 9 Homework #19-34

How do you convert between moles and mass of a compound?!

Calculating Molar Mass

The mass of one mole of a compound.

Units: g/mol Example 1: NaCl Example 2: CO2

Example 3: C8H10N4O2 (caffeine!)

Calculate the molar mass…

1. lithium bromide2. aluminum carbonate3. acetic acid (CH3COOH, the acid in

vinegar)

A: Homework

Week 9 Homework #27-34: Mon. Bring your calculator every day!

Converting between moles and mass of compounds Example 1 Calculate the mass of 4.52 moles of

lithium bromide.

Example 2

Calculate the number of moles equal to 1.00 grams of aluminum carbonate.

Example 3

Calculate the mass of 0.500 moles of acetic acid.

1. Calculate the mass of 20.0 moles of lithium bromide.

2. Calculate the number of moles equal to 100.0 grams of aluminum carbonate.

3. Calculate the mass of 0.400 moles of acetic acid.

Mass to moles to molecules

Ex. 1: Calculate the mass of 12,000. molecules of lithium bromide.

Ex. 2: Calculate the number of molecules of aluminum carbonate in 100 grams of the compound.

1. Calculate the mass of 3.00x1020 molecules of lithium bromide.

2. Calculate the number of molecules of aluminum carbonate in 45.0 grams of the compound.

3. Calculate the mass of 1,200.0 molecules of acetic acid.

4. Calculate the number of molecules of acetic acid in 10.0 grams of the compound.

Homework: Week 9 Homework #

MOLES CONVERSIONS STATIONS

Directions

When you receive a sample, find the correct box on your worksheet.

Instructions

Front side: A. Find the mass of the sample

(subtract the mass of the container)

B. Convert the mass to moles. C. Convert the moles to number of

atoms or molecules.

Back side: A. Record the number of atoms or

molecules on the card. B. Convert that to moles. C. Convert moles to mass (grams). D. Find the mass of the sample

(subtract the mass of the container), and compare to your calculated mass.

Work quickly. 7 minutes per station!

Pass the sample and card to the next table when the timer goes off.

Due at the end of the period.

Practice Moles to Number of Atoms Conversions

1. How many moles of vanadium are in 4.5 x 102 atoms of V?

2. How many moles of oxygen gas are in 45,000 molecules of O2?

3. How many moles of neon are in 1.2 x 103 atoms of Ne?

4. How many moles of chromium are in 7.90 x 1021 atoms of Cr?

Atoms to Moles

How many atoms of sodium are in 0.5 moles of sodium?

How many atoms of oxygen are in 1.5 moles of oxygen?

How many atoms of fluorine are in 0.075 moles of fluorine?

How many atoms of argon are in 3.45 moles of argon?

Converting between mass (g) and moles (mol)

1 mol O15.999 g O

Or15.999 g O1 mol O Choose one depending on if you are

given grams of oxygen or moles of oxygen.

Lithium (Li) Calculate the mass of 3.0 moles of

lithium. How many atoms are there in 3.0

moles of lithium?

Chromium (Cr) Calculate the number of moles of

chromium if you had 3.25x1034 atoms of chromium.

Calculate the mass of 3.25x1034 atoms of chromium.

Zinc (Zn) How many moles of zinc are there in

34.7 grams of zinc? How many atoms of zinc in 34.7

grams?

Write both fractions.

Germanium (Ge) Calculate the mass of 3.0 moles of

germanium. How many atoms is that?

Which Fraction?

How many moles of chlorine are in 6.4 grams of chlorine?

Which Fraction?

How many grams of krypton are in 8.9x1012 moles of krypton?

How many atoms is that?

Which Fraction?

How many grams of hydrogen are in 32.1 atoms of hydrogen?

How many moles is that?

Which Fraction?

How many moles of aluminum are in 6.5 grams of aluminum?

Which Fraction?

What is the mass of 5.6x103 moles of mercury?

How many atoms is that?

Write both fractions.

How many moles are equal to 2.58x1067 atoms of Xenon (Xe)?

Calculate the mass.

Which Fraction?

How many moles of Xe are in 9.0 grams of Xe?

How many atoms is that?

Molar Mass Practice1. What is the mass in grams of 3.50 mol

of copper (Cu)? 2. What is the mass in grams of 2.25 mol

of iron (Fe)?3. What is the mass in grams of 0.375 mol

of potassium (K)?4. What is the mass in grams of 0.0135

mol of sodium (Na)?5. What is the mass in grams of 16.3 mol

of nickel (Ni)?

How many moles of Aluminum are in 11.9 grams of Aluminum?

How many moles of calcium (Ca) are in 5.00 grams of calcium?

How many moles of copper (Cu) are in 13.3 grams of Copper?

How many moles of gold (Au) are in 3.60 x 10-10 grams of gold?

Mass to atoms

1. What is the mass in grams of 1.20 x 108 atoms of copper?

2. What is the mass in grams of 7.5 x 1015 atoms of nickel?

3. How many atoms of sulfur are in 4.00 grams of sulfur?

4. How many atoms of carbon are in 1500 grams of carbon?