Ions and Isotopes

Warm Up1. What’s the difference

between a unicycle, a bicycle and a tricycle? (aren’t they the same thing?)

2. How many protons, neutrons, and electrons does Oxygen have?

Objetivos• SWBAT distinguish

between atoms, isotopes, and ions.

• SWBAT calculate number of protons, neutrons, and electrons.

Agenda• Warm Up• Agenda• Revisit Atom• Fruit Loopy Atoms?• Ions & Isotopes• WS.4.2• Exit Ticket

Quiz tomorrow

Activity: Fruit Loopy Atoms Date

Background Info

Subatomic Particles

• Proton – heavy and +1 charge• Neutron – heavy and 0 charge• Electron – tiny and -1 charge

Electron ShellsElectron shell – orbit followed by electrons around

an atom’s nucleus.

How electron shells fill:

ELECTRON SHELL MAX NUMBER OF ELECTRONS

1ST 22ND 83rd 184th 32

Picture of a Beryllium Atom

Beryllium Atomic number:

Protons:Neutrons:Atomic mass: 9

• Atom = most common form of element, atoms are ALWAYS neutral (# protons = # electrons)

An atom has 5 protons … How many electrons does it have?

How can we tell atoms of different substances apart?

• Each type of atom has a different number of PROTONS

• ATOMIC NUMBER = # of PROTONS… what defines an element!

An atom has 82 protons … what element is it?

• Look for number 82 on your periodic table!!

How many electrons does it have?

• Atomic # = # Protons = # Electrons• 82 = 82 protons = 82 electrons

You Try!

Element Atomic Number Protons Electrons

8

So … in atoms protons = electrons

What about neutrons???

Atoms have DIFFERENT amounts of Neutrons!!

They are called ISOTOPES

Isotope = atoms with same # protons, different # of neutrons

How can we figure out how many neutrons an atom has?

The mass of an atom can be calculated by adding protons + neutrons!

Mass Number (sometimes all called “atomic number”) = # protons + # neutrons

Practice

Element Atomic Number (Protons!!!) Mass Number Neutrons

Neon 22 ?

Practice

Element Atomic Number Mass Number Neutrons

20 46

Atomic Weight

• Mass Number/Atomic Mass is not to be confused with atomic weight!

• Atomic weight = weighted average of the atomic masses of the different isotopes of an element

• Where is atomic weight on your PToE?

16

S32.065

Ion

• Ion = an atom that has either lost or gained electrons and now has a + or - charge

• Materials/Methods: You will build an atom from the periodic table using a paper plate, fruit loops, and glue. It is important that you both use the same color for the same sub atomic particles.

Pick your Partner

• Choose someone who know you will work well with

• Move to a desk beside them

Fruit Loop Atoms

• Complete first part of the Fruit Loop Activity• When you reach a , you should probably stop.

•Make an ATOM of Lithium, Beryllium, or Boron

Isotope

An isotope is an atom with the same # of protons and electrons but a different # of neutrons.

Example: The most common type of sulfur usually has 16 neutrons, but sometimes an isotope of sulfur will have 17 neutrons.

** Number of protons and electrons the same!

Notes

Isotope

Scientists like to have a quick way to write down isotopes! There are two ways:

C – 14 Mass Number

Notes

H21

Mass Number

Example

• Write the isotope symbol in two ways for an isotope of fluorine that has a mass number of 22.

You Try!You Try! Notes

IsotopeElement Symbol Atomic Mass Protons Neutrons Electrons

Sr - 92

Cr – 60 24

Gold 203 79

Fill out the chart with your partner, then make a fruit loop isotope for

Li – 9, Be – 11, B - 14.

Notes

Ion

An ion is an atom with the same number of protons and neutrons but a different number of electrons.

This means the charge is no longer neutral!

Two types: Cation = positive ion, lost electronsAnion = negative ion, gained electrons

Notes

Ion

Meet the atom’s family!

Symbols:

C4- F1+

Notes

New Electric Charge

IonElement Symbol Atomic Mass Protons Neutrons Electrons

Sr 2+

Cr3+ 24

Fluorine 19 10

Fill out the chart with your partner, then make a fruit loop Ion.

Li1+, Be2+, B2-. **Use the same # of neutrons as

when you made the original atom.

Notes

Conclusion

• 1. How are each of your three atoms different?• 2. Why are the masses of the atom of the element and

the isotope different?• 2. Calculate the average weight of your element. (Take

the average of the atomic mass of the original atom and the atomic mass of the isotope.) Average weight= __________________________________

• 3. Are the atomic weights on the periodic table whole numbers or decimals?

• 4. Why do you think the atomic weights are this way?

Complete WS 4.2

Warm Up1. You have 3 skittles. The

mass of all the skittles is 9 g. What is the mass of each skittle?

2. A bag of M&M’s has 40 M&M’s. There are 10 blue M&M’s. What percentage of all the M&M’s are blue?

???• EQ: How do we calculate

average atomic weight?• HOT Q1: What does

percent abundance mean?

• HOT Q2: Why are the atomic weights on the PToE decimal numbers?

• HOT Q3: What terms do we need to define for our quiz?

Agenda

• Warm Up • Agenda• Beanium• Quiz!• Exit Ticket

Beanium

• On a periodic table, the values for atomic number and atomic weight are given for each element. The atomic number is the whole number and represents the number of protons in the atom. The atomic weight is a decimal number because it represents a weighted average of the masses of the isotopes of each element.

• In the following lab, you will determine the average atomic weight for the element “beanium”. There are three naturally occurring isotopes of beanium: white-beanium (must have a black dot!), brown-beanium, and speckled-beanium. You will calculate the average atomic weight of a given sample of beanium.

When You Get to Your Lab Station…

• READ the directions

• If you are confused– 1) THINK– 2) Ask a person at your lab station BEFORE you ask

Ms. Hoffman – 3) Ms. Hoffman is your last resort

At the lab station…

• You are 30 minutes to complete this activity

• By the end of 30 minutes, you have answered ALL questions on lab handout

Classroom Leaders!• People I will be pulling out to meet with:

– Tucker– Ken’Dajha– Nigel– Kiana– Justin– Jalisa– Jenn– Aysha– Krishanni– Nevada– Josh

Beanium• 1. Separate the “atoms” of beanium in your

sample into three groups based on type of isotope (white, brown, or speckled). THROW OUT ALL WHITE BEANS THAT DO NOT HAVE A BLACK DOT. Count the number of atoms of each isotope and record below:

Isotope # of Atoms

White Beanium Atoms

Brown Beanium Atoms

Speckled Beanium Atoms

• 2. Using your balance, find the mass of each isotope in the sample and record below:

Isotope Total MassWhite Beanium AtomsBrown Beanium Atoms

Speckled Beanium Atoms

• 3. Calculate the grams in one atom of each isotope and record below. To find the mass of one atom of beanium – divide the total mass by the number of atoms you have for that element. Example: Total Mass of White Beanium / # of White Beanium Atoms

Isotope Atomic MassWhite Beanium AtomsBrown Beanium Atoms

Speckled Beanium Atoms

4. Determine the percent abundance of each isotope in your sample. This can be done by

dividing the number of atoms of each isotope by the total number of atoms in your

sample and multiplying by 100. Example: ( # of white beanium atoms / Total #

of atoms ) * 100Isotope % Abundance

White Beanium AtomsBrown Beanium Atoms

Speckled Beanium Atoms

Vocab Quiz!• Define the following terms:–Proton–Neutron–Electron–Atom–Atomic Number– Isotope–Mass Number (also called “atomic mass”)– Ion

Quiz!• Define the following terms:– Proton– Neutron– Electron– Atom– Atomic Number– Isotope– Mass Number (also called “atomic mass”)– Ion– Cation– Anion

Practice

Substance: HeliumSymbol: HeAtomic Number: 2Mass Number: 4Number of Protons: Number of Neutrons: Number of Electrons:

Substance: MagnesiumSymbol: Atomic Number: 12Mass Number: 24Number of Protons: 12Number of Neutrons: Number of Electrons:

Substance:Symbol: ZnAtomic Number: 30Mass Number: 65Number of Protons: Number of Neutrons: Number of Electrons:

Substance: BromineSymbol: BrAtomic Number: Mass Number: 80Number of Protons: Number of Neutrons: Number of Electrons: 35

Substance: Symbol: Atomic Number: 13Mass Number: Number of Protons: 14Number of Neutrons: 14Number of Electrons:

Substance: UraniumSymbol: UAtomic Number: Mass Number: Number of Protons: Number of Neutrons: 146Number of Electrons: 92

Substance: SodiumSymbol: Atomic Number: 11Mass Number: Number of Protons: Number of Neutrons: 12Number of Electrons:

Substance: KryptonSymbol: KrAtomic Number: Mass Number: Number of Protons: Number of Neutrons: 48Number of Electrons: 36

Substance: Symbol: CaAtomic Number: Mass Number: 40Number of Protons: 20Number of Neutrons: Number of Electrons:

Substance: Oxide ionSymbol: O2-

Atomic Number: 8Mass Number: 16Number of Protons: Number of Neutrons: Number of Electrons:

Substance: ChlorideSymbol: Cl-1

Atomic Number: Mass Number: 35Number of Protons: Number of Neutrons: 17Number of Electrons:

Substance: Strontium ionSymbol: Sr 2+

Atomic Number: Mass Number: 36Number of Protons: 18Number of Neutrons: Number of Electrons:

Exit Ticket

Use your periodic table of awesomeness!

1. What is the “average atomic weight”?

2. What is the mass number of C – 15?

3. How many neutrons does C-15 have?