1. Tuesday January 26th, 2016
By the end of the day, Scholars will be able to:
Starter:
Match the following scientists to their respective discoveries:
Describe the three major subatomic particles and determine the number of each for an element
Democritus
Dalton
Rutherford
Thomson
Chadwick
Atomic theory
Electron
Nucleus/ Proton
Neutrons
Earliest thought of the atom
And answer a question like this:
List the number of protons, electrons, and neutrons for the element Rb.
Topic: The Atom
8-10 minutes

2. Elements 1-10 Quiz
Neon
Carbon B He
Fluorine
Nitrogen Be O
Lithium H

3. What is an atom?
Atom
The smallest particle of an element that retains the chemical properties of that element

4. The Atom
Atoms are very small, and they are made up of even smaller subatomic particles.
Proton
Neutron
Electron

5. The Atom Particle Charge Mass Location Proton +1 heavy nucleus Neutron
Electron -1
light
Outside the nucleus

6. What is in an atom?
Each element has a unique number of protons.
Unreacted atoms have no overall charge.
The electric force holds the atom together.
Positive protons are attracted to negative electrons by the electric force.

7. Atomic Number
The atomic number is the number of protons in the nucleus of an atom.
For neutral atoms, the atomic number also describes the number of electrons outside of the nucleus.

8. Atomic Weight
The atomic weight is a measurement of the total number of particles in an atom’s nucleus.
It is a weighted average of all of the naturally occurring isotopes of an element.

9. Atomic Mass/Mass Number
The atomic mass is the sum of the number of neutrons and protons in the nucleus of an atom.
It is not always the same as the number on the periodic table.
Atomic mass= protons+ neutrons

10. Summary For any element (neutral): # of protons= atomic number
# of electrons= atomic number
# of neutrons= atomic mass - # of protons
Atomic Mass/Mass Number= #protons + #neutrons

11. Practice B 6 11 24 31 37 29 35 43 100 Symbol Atomic # Protons Neutrons
Electrons
Atomic Mass B 6 11 24 31 37 29 35 43
100

12. Isotopes
Isotope: atom that is missing a neutron or has an extra neutron
The most common form of carbon found is carbon- 12 which has 6 neutrons.
Two isotopes of carbon are
Carbon-13 which has 7 neutrons
Carbon-14 which has 8 neutrons (used for carbon dating).

13. Example: Two Isotopes of Sodium

14. How are isotopes represented?
X: element symbol
How are isotopes represented?
A: Mass Number
#protons + # neutrons in the nucleus
Always larger than Z
Z: Atomic number
#protons

15. Isotopes of Sodium Na 11 23 Na 24 11

16. 2 Ways to write Isotope Symbol
Mass Number
2 Ways to write Isotope Symbol Na 11 23
element symbol
Mass Number
Or Sodium-23
Atomic number

17. Class Problem
Write the isotope symbol for the chemical element that has 6 protons and 8 neutrons (write the symbol both ways)

18. How many atoms are in 3 moles of As?
Tuesday January 26th, 2016
By the end of the day, you will be able to:
Starter:
Convert from grams to atoms.
Symbol
Atomic Number
Protons
Neutrons
Electrons
Atomic Mass 29 64
O-2 8 25 24 55 Na 12 11 10 22
And answer a question like this:
How many atoms are in 3 moles of As?
Topic: Atom Conversions

19. Quick review: Convert 450 meters to miles
(given 1km=1000m, km = 1 mile)

20. The mole The mole is useful for counting small particles.
mole: the SI base unit used to measure the amount of a substance whose number of particles is the same as the number of atoms of carbon in exactly 12 g of carbon-12 (abbreviation, mol)
A mole is 6.02 x 1023 of an item
A mole of paperclips is 6.02 x1023 paperclips
A mole of couches is 6.02 x 1023 couches
6.02 x 1023= 602,000,000,000,000,000,000,000
Six-hundred-two sextillion

21. Known as “Avogadro’s Number”
Named after Amadeo Avogadro

22. \

23. Moles
In chemistry, the mole is the standard unit of measurement of amount.
But do balances automatically measure in moles?
NO, so we have to do a little converting using the periodic table!

24. Calculating Molar Mass
Moles and grams are related.
molar mass = the mass in grams of one mole of a substance
Example: 1 mol of carbon-12 atoms has a mass of g, so the molar mass of carbon-12 is g/mol
Practice:
Fe: H:
Hg:

25. Atomic Masses, continued
Compounds also have molar masses.
To find the molar mass of a compound, add up the molar masses of all of the atoms in a molecule of the compound.
Example: finding the molar mass of water, H2O
molar mass of O = g/mol
molar mass of H = 1.01 g/mol
molar mass of H2O = (2 × 1.01 g/mol) g/mol = g/mol
Practice
NaOH
Hcl

26. Converting from Grams to Moles
There are three steps to converting from grams of a substance to moles of a substance.
Determine how many grams are given in the problem.
Calculate the molar mass of the substance.
Do the math.

27. Practice Problems 1) 2.00 moles of H2O 2) 75.57 grams of KBr
3) 100. grams of KClO4
4) 8.76 moles of NaOH
5) grams of Na2CO3

28. Calcium Al S Potassium Magnesium Ar Si Phosphorus Sodium Chlorine
Element Quiz
Calcium Al S
Potassium
Magnesium Ar Si
Phosphorus
Sodium
Chlorine

29. Grams to Atoms Conversions
How many atoms are in 720 g of C6H12O6?
How many grams are there in 6.02x1023 atoms of Aluminum?
Convert 60.2x1023 atoms of Barium into grams.

30. How many moles are in 5g of NaOH?
Friday January 30th, 2015
By the end of the day, Scholars will be able to:
Starter:
Do the following conversions:
How many moles are in 65 x atoms of Fe?
How many molecules are in 5 moles of paperclips?
Convert from grams to atoms.
And answer a question like this:
How many moles are in 5g of NaOH?
Topic: Atom Conversions/ Avagadro’s Number
8-10 minutes

31. How many atoms are in 5g of NaOH?
Monday February 2nd, 2015
By the end of the day, Scholars will be able to:
Starter:
Calculate the molar masses:
AlCl3
BaBr2
How many moles are in g of Fe2O3?
How many atoms are there in 3 moles of Carbon?
Convert from grams to moles using the molar mass for the element or compound.
And answer a question like this:
How many atoms are in 5g of NaOH?
Topic: Mole Conversions
8-10 minutes

32. How many atoms are in 5g of NaOH?
Tuesday February 3rd, 2015
By the end of the day, Scholars will be able to:
Starter:
How many moles are in 72.9 g of HCl?
How many atoms are in 8550g of SO2?
Convert g of LiBr to atoms.
Convert from grams to moles using the molar mass for the element or compound.
And answer a question like this:
How many atoms are in 5g of NaOH?
Topic: Mole Conversions
8-10 minutes