Unit 2 Study Guide

Atomic Structure & the Periodic Table

E1. Trace the development of models of the atom to the present and describe how each model reflects the scientific understanding of their time.

E6. Compare the physical and chemical characteristics of elements.

E7. Describe nuclear reactions, including fusion, fission, and decay, their occurrences in nature, and how they can be used by humans.

Activity #1 – Atomic Structure

Read ATOMS AROUND US.

1. Fill in the blank: All elements are made of ______________.

Read ATOMS = BUILDING BLOCKS.

2. Label the major subatomic particles in the atom on the diagram below.

3. Fill in the blanks: The ___________ and ____________are always in the center of the atom. Scientists call the center of the atom the ________. The _________ are always found whizzing around the center in areas called __________.

4. What do the “0”, “-“, and “+” refer to on the diagram above?

Activity #2 – Atomic Builder

The stuff you scrape off burnt toast is made primarily of atoms of carbon. But what makes up a carbon atom -- or any other atom?

Here's a chance for you to construct a carbon atom. You'll start with a hydrogen atom, which contains one proton and one electron. Just add protons, neutrons, and electrons. By the way, you must also build each proton and neutron from two types of quarks -- up quarks and down quarks. Finally, some advice: try to keep the particles' charges balanced. You'll have a difficult time if you don't. Before you start, answer the questions below.

Read The Atom Builder Guide to Elementary Particles.

1. In activity #1, you learned about the three major subatomic particles. It turns out that protons and neutrons are made of even smaller particles. What are these particles called?

2. Record the color code in the picture of an atom on this page (you will need it later). What color represents the
1. protons? ____________
2. neutrons? ____________
3. electrons? ____________

3. Fill in the “recipes” for the nucleons (particles found in the nucleus) below:

1 proton = ____ up quark(s) + ____ down quark(s)

1 neutron = ____ up quark(s) + ____ down quark(s)

Read The Atom Builder Guide to Building a Stable Atom.

4. Fill in the blanks: A stable atom has a net charge of _______. In other words, it has an equal number of _________ and ________.

5. When is an atom ionized? Why don’t you want this to happen in this activity?

6. When does an atom become radioactive? Why don’t you want this to happen in this activity?

7. Up to how many electrons can occupy
1. the 1^st shell _______?
2. the 2^nd shell _______?

Now you are ready to build a carbon atom! Open the Atom Builder.

8. Construct a neutron from the up and down quarks in the “Nucleon Assembly” area. Move this to the hydrogen nucleus on the right. Did adding a neutron change hydrogen into helium?

9. Construct another neutron from the up and down quarks in the “Nucleon Assembly” area. Move this to the nucleus on the right. What happened to the atom?

10. Construct a proton from the up and down quarks in the “Nucleon Assembly” area. Move this to the hydrogen nucleus on the right. Did adding a proton change hydrogen into helium? What else happened?

11. Add an electron to the atom. Try putting it in the 2^nd energy level (the outer circle). What happens? Where does the electron end up?

12. At this point you should have a stable helium atom. How many electrons _____? Protons _____? Neutrons _____?

13. Add another electron to the atom. Try putting it in the 1^st energy level (the inner circle). Are you allowed to do this? Why or why not?

14. Continue building your atom in this manner until you have constructed a stable carbon atom. Show your carbon atom to your teacher and have her initial below.

Teacher’s initials _____________

How many electrons _____? Protons _____? Neutrons _____?

Activity #3 – Dream Journey into the Atom (The Particle Picture)

You will need to use the poster here. (You may get a print-out of this poster from your teacher if you wish.) Matter is made of tiny particles. And those particles are made of even tinier particles ... Name the particles described in the clues. You will find all of the answers in the poster.

1	Brownian motion: You see these microscopic specks of dust or smoke moving around ...
2	... because we believe they are pushed about by these particles of the air ...
3	... which are made up of these particles of oxygen and nitrogen.
4	JJ Thomson discovered these particles ...
5	... which orbit around this particle at the center of every atom ...
6	... which is made up of these positively-charged particles ...
7	... and these uncharged ones ...
8	... which are made up of these even tinier particles.

Now, use the 11 letters in the highlighted boxes to make a word which is the name of a machine used for making sub-atomic particles move faster.

At the start of the twentieth century, there was no way that scientists could hope to see individual atoms. Indeed, many scientists still did not accept that matter was made of atoms.

Activity #4 – Dream Journey into the Atom (Changing Pictures)

At the start of the twentieth century, there was no way that scientists could hope to see individual atoms. Indeed, many scientists still did not accept that matter was made of atoms. Since then, some very clever experiments have allowed us to find out a lot more about the structure of atoms. Our picture of the atom has changed a lot.

(You will find the answers to these questions in the poster.)

1) Model 1: The ‘pudding’ model

In the pudding model:

a) What is the dough? What charge does it have?

b) What are the currants? What charge do they have?

c) Why must there be equal amounts of positive and negative charge?

2) Model 2: The ‘nuclear’ model

In the nuclear model:

a) What is at the center of the atom? What charge does it have?

b) What particles orbit around the outside? What charge do they have?

3) Changing models

Ernest Rutherford suggested an experiment to test the pudding model.

a) What metal did he use as his target?

b) Which particles did he fire at the target?

c) What was the source of the particles?

d) If the pudding model was correct, what would happen to the particles?

e) What was the surprising result of the experiment?

f) How did Rutherford account for this result?

4) Changing ideas

The word atom means indivisible.

a) Is an atom indivisible?

b) Why do you think we stick with the word atom?

Activity #5 – Dream Journey into the Atom (Particles & People Puzzle)

Use the poster to solve these clues:

1. In 1897, I made a beam of electrons in a vacuum tube. Who am I?

2. You’ll find me in an atom and in a lightning flash. I sometimes travel along wires. I’m naturally negative! What am I?

3. It was a surprise to me when an alpha particle bounced back! My prediction was completely wrong! Who am I?

4. I may be small, but I’m a lot heavier than those electrons. Maybe that’s why they orbit around me! What am I?

5. I’m using electrons to study what is inside protons. Who am I and where do I work?

6. I am one of these: a molecule, a proton, an electron, an atom or a nucleus. I’m the only one of these who isn’t made up of other particles. What am I?

7. Jude uses me in a beam with loads of others just like me so that she can look into new materials. What am I?

8. I work on the world’s biggest particle accelerator looking for answers to big questions. Who am I and where is the accelerator?

9. Gavin is working on me. I am going to be the new version of the World Wide Web! What am I?

10.I use work done in particle physics experiments to make better X-ray detectors which should help us to treat cancer. Who am I?

The next two of these have answers but not clues! Can you think of good clues for them?

11.	Quark
12.	Molecule

Activity #6 – Ions, Atomic Number, Atomic Mass and Isotopes

1. On this page:

1. Define atomic number.

2. Click “extra”. What defines the identity of an element?

3. If you add a proton to sodium, what element do you have? What is its atomic number?

4. If you subtract a proton from sodium, what element do you have? What is its atomic number?

2. On this page:

1. define ion:

2. define cation:

3. define anion:

4. If you remove an electron from a neutral atom, does it become positive or negative?

5. If you add an electron to a neutral atom, does it become positive or negative?

3. On this page:

1. Define mass number.

2. You can figure out the number of neutrons in an atom of oxygen by subtracting its _____________ (the number of protons) from its _____________.
3. How many neutrons are there in an oxygen atom with an atomic mass of 16? ________
4. How many neutrons are there in a sodium atom with an atomic mass of 23? ________

4. On this page:

1. Define isotope.

2. The standard format for writing an isotope is shown above, where A is the __________ number ( __________ + __________ ) and Z is the __________ number (number of __________ )

3. For a neutral atom of boron-10, what is the

1. mass number _____

2. atomic number _____

3. number of protons _____

4. number of neutrons _____

4. For boron-11, what is the

1. mass number _____

2. atomic number _____

3. number of protons _____

4. number of neutrons _____

5. On this page:

1. Define atomic mass.

2. The units for atomic mass are ____________________, or _____.

3. One amu is defined as ____________ the mass of a __________ atom (specifically the carbon-12 isotope). Therefore, the mass of one atom of carbon-12 is exactly ________ __________.

4. How do you get the mass of boron (10.81 amu) that is found on the periodic table? Do the calculation below:

1. boron-10 is found in nature 19% of the time so

0.19 X 10.00 amu = ______

2. boron-11 is found in nature 81% of the time so

3. 0.81 X 11.00 amu = ______

4. to get the average atomic mass of all the isotopes of boron found in nature, add #1 and #2 above = ______

6. Quiz yourself: What element in the periodic table
1. has 23 protons? ________
2. has an atomic mass of 14? ________
3. has 12 electrons in a neutral atom? ________
4. has 16 electrons in its -1 anion? ________
5. has two isotopes, one with a mass of 35 amu (77.5% abundance) and one with a mass of 37 amu (22.5% of the time) ________


7. Quiz yourself:

Activity #7 – Electron Shells

Fill in the blanks using this website.

Electrons are arranged around the ______________ in ______________. For simplicity they can be thought of like mini-planets orbiting a central sun, but it is closer to the truth to think of them as "clouds" of electric charge around the Nucleus.

The shells are numbered ___________ from the Nucleus. Fill in the maximum number of electrons found in each shell in the table below.

Shell Number	Maximum Number of Electrons in the Shell
1
2
3
4
5

The Octet Rule:

In general, atoms are most stable when they have_________ electrons in their outer-most shell. ( ______ means 8.) The exception is the ____________ shell which is most stable with _________ electrons.

If you know the ___________ ___________ and ______________ ___________ of an element and the maximum number of electrons in each electron shell you can draw a diagram of the element.

For example: Sodium has an Atomic Number of 11 and an Mass Number of 23.
This means an atom of Sodium has __________ Protons and therefore ________ electrons.

Since the number of Protons + Neutrons is __________ and there are _________ Protons there must be ________ Neutrons.

From the table above the electrons are arranged as: First Shell = __________, Second Shell = _________, Third Shell = ________ (Giving a total of __________.)

Example 2: Chlorine has a Mass Number of 35 and an Atomic Number of 17.

This means an atom of Chlorine has ___________ Protons and therefore _________ electrons.

Since the number of Protons + Neutrons is __________ and there are _________ Protons there must be __________ Neutrons.

From the table above the electrons are arranged as: First Shell = __________, Second Shell =__________, Third Shell = __________ (Giving a total of _________.)

Activity #8 – A Periodic Table of Colors

1. Open this article. Fill in the blanks

The periodic table is organized like a big ________. The elements are placed in specific places because of the way they _________ and ___________. If you have ever looked at a grid, you know that there are __________ (left to right) and _____________ (up and down). The periodic table has rows and columns, too, and they each mean something different.

2. Open The Periodic Table of Colors. Make a periodic table of colors by arranging them into groups and periods that have similar properties.

Note in the pictures above, that periods are horizontal rows and groups are vertical columns. In a periodic table, elements that are in the same periods and groups have similar properties. A periodic table is also arranged in a way that shows periodic or recurring trends in the properties of elements.

Your periodic tables of colors should be arranged in a way that clusters colors and intensities with similar properties into rows and columns and also shows trends as you go from left to right across groups and from top to bottom down periods.

After you have finished your periodic table, have your teacher initial here ______.

1. How did you decide which colors to put in the same group?

2. How did you decide which colors to put in the same period?

3. What trend(s) do you have as you go down groups?

4. What trend(s) do you have as you go across periods?

Activity #9 – Color Coding the Periodic Table

Color code the attached periodic table according to the instructions below:

1. Make the dividing line (the zig-zag looking staircase) between the metals and nonmetal more visible by using a highlighter or colored pencil.
2. Label each side with arrows. “Metals” on the left and “Nonmetals” on the right.
3. “Metalloids” are the elements that touch the staircase line on one side. Draw diagonal lines in the metalloids boxes as shown below and label “Metalloids”.

4. Make a key at the bottom of the periodic table using four different colors (see above).
5. Color the boxes of the two liquid elements according to your key. Their atomic numbers are 35 and 80.
6. Color the eleven gas elements – atomic numbers 1, 2, 7, 8, 9, 10, 17, 18, 36, 54 and 86.
7. Color the twenty synthetic or manmade elements – atomic numbers 43, 61, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109 and 110.
8. Use the fourth color to OUTLINE ONLY the boxes containing the twenty-nine radioactive elements. – atomic numbers 43, 61, 84, 85, 86, 86, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109 and 110.
9. Near the top of the page, label the groups and periods with arrows as shown below.

10. Above group 1A, in the box, write the number of electrons in the outer shell which is 1. Continue across the top with the remaining numbers of electrons as shown in the table below.

column number	1A	2A	3A	4A	5A	6A	7A	8A
# of electrons in the outer shell	1	2	3	4	5	6	7	8

11. Write the number of energy shells in the boxes in the period column. Hint: the top row is 1 and the bottom is 7.

Activity #10 – Metals, Nonmetals, & Metalloids

Read this website and then write “metal”, “nonmetal”, or “metalloid” on the blanks next to the properties.

1. _______ semiconductors (are not the best or worst conductors)
2. _______ on the right side of the periodic table
3. _______ typically shiny
4. _______ good conductors of heat and electricity
5. _______ low density
6. _______ can be shiny or dull
7. _______ malleable (bendable, can be pounded into sheets
8. _______ will corrode
9. _______ dull surface
10. _______ high density
11. _______ poor conductor of heat and electricity
12. _______ are along the staircase dividing line on the periodic table
13. _______ most elements on the periodic table are this
14. _______ will melt at low temperatures
15. _______brittle
16. _______ have properties of both metals and nonmetals
17. _______ only melt at high temperatures
18. _______ ductile (can be drawn into wires)

Activity #11 – Chemical Families

Do the following crossword puzzles. You will find the links to them on this page. After you are done, answer/do the following:

1) In what group number, would you find the:

a) alkali metals _____

b) alkaline earth metals _____

c) chalcogens _____

d) halogens _____

e) noble gases _____

2) Label the above groups on your colored periodic table.

Activity #12 – Review Games and Worksheets

1. Element Math Game - Choose the following options and then click “I’m ready! Let’s start!:

When you finish, click “All Done” to get your results. Show your results to your teacher and have her initial here ___________.

2. Element Word Scramble - Play the fifteen question version with clues. After you finish, show your teacher the “Results” screen and have her initial here: _________

3. Periodic Table Jeopardy - After you finish, show your teacher your score and have her initial here: _________
4. ATOMIC STRUCTURE, ISOTOPES and ELECTRON STRUCTURE - Enter your answers in the form online as well as below so that you can check your answers.

   15    2    2    2.7    2.8.5    21    21    22    26    26    2nd    3    30    4th    5    5th    7    8    8    9    atomic    atomic    electrons    electrons    electrons    group    iron    isotopes    mass    mass    neutrons    neutrons    nucleus    number    period    shell    shells    three    

Top of Form

Q1(a) Atoms are made of fundamental particles called protons (+), (0) and (-). (b) The centre of the atom is called the . (c) It consists of protons and and contains most of the mass of the atom.

Q2(a) The number of protons in the atom is called the number. It also equals the number of in a neutral atom. (b) The is the sum of the protons and neutrons in the nucleus.

Q3 An atom of mass number 43, and atomic number 21, consists of protons, neutrons and electrons.

Q4 (a) In the symbol for an atom of shown on the left, the atom consists of protons, neutrons and electrons. (b) Atoms of the same element with a different number due to different numbers of neutrons are called .

Q5(a) Electrons are arranged around the nucleus in energy levels or . (b) The 1st shell can have a maximum of electrons, the shell a maximum of electrons and the 3rd shell a maximum of electrons. (c) The 19th and 20th electrons go in the shell. (d) The electron arrangement, showing the number of electrons in each can be written out in shorthand eg 2.8.6 for the 1st, 2nd and 3rd shells respectively.

Q6(a) Apart from hydrogen and helium in period 1 of the Periodic Table the last number in the arrangement is equal to the number in the Periodic Table. (b) The number of shells used containing electrons is equal to the number. (c) The number of electrons in an atom is equal to the or proton number.

Q7(a) Phosphorus has an atomic number of 15 so the atoms have protons or 15 . (b) The electron arrangement will be . (c) In the Periodic Table it will be a member of Group and it will be the element along Period .

Q8(a) Fluorine has an atomic number of so the atoms have 9 protons or electrons. (b) Its electron arrangement is and it belongs to Group on Period .

Bottom of Form

5. THE PERIODIC TABLE - Enter your answers in the form online as well as below so that you can check your answers.

   +1    -1    0    1    1    1    2    2    7    alkali    atomic    balloons    before    boiling    brittle    catalysts    coloured coloured    covalent    densities    diatomic    down    dull    electronic    electrons    floats    gases    gases    gases    greater    groups    halide    halogens    heat    heat    heat    high    higher    hydrogen    hydrogen    hydroxide    inert    ionic    left    less    less    less    level    liquid    liquid    low    low    lower    mass    mercury    metals    metals    metals    more    more    noble    non-metals    non-metals    number    period    periods    poor    properties    right    same    shiny    similar    similarities    single    solids    transition    unreactive

Top of Form

Q1(a) The chemical elements in the Periodic Table were originally arranged in order of the atomic .
(b) This list can then be arranged in rows so that elements with properties are in the same columns, known as .
(c) The complete horizontal rows of disimilar elements are called .

Q2(a) Although most elements are in appropriate Groups, a few are not.
(b) Argon atoms, for example, have a relative atomic mass than potassium atoms but argon is better placed potassium in the periodic table so that it is in Group and potassium is in Group .
(c) In the modern periodic table elements are arranged in order of their or proton number.

Q3(a) The periodic table can be seen as an arrangement of the elements in terms of their electronic structure.
(b) From left to right, across each of the periodic table, a particular energy is gradually filled up with and in each successive period, the next energy level is filled with electrons.
(c) The and differences between the of elements in the same group of the periodic table can be explained by the structure of their atoms.
(d) Elements in the same group have the of outer electrons.

Q4(a) The elements in Group of the periodic table are known as because they form hydroxides which dissolve in water to give alkaline solutions.
(b) They react with to form ionic compounds in which the metal ion carries a charge of .
(c) In Group 1, the further down the group an element is - the reactive the element; the its melting point and boiling point.
(d) When a piece of lithium, sodium or potassium is placed in cold water the metal , and may melt and move around the surface of the water with fast fizzing!
(e) The metal reacts with the water to form a metal solution and gas.

Q5(a) Fewer than one quarter of the elements are .
(b) Non-metal elements are found in the Groups at the hand side of the periodic table.
(c) The elements in Group 7 and Group 0 have the typical properties of non-metals - they have melting points and boiling points (at room temperature all the Group 0 elements are ).

Q6(a) The Group elements are called the The first two are and the third, bromine, is a ).
(b) They are and crumbly when solid and are conductors of and electricity even when solid or liquid.
(c) These elements have vapours and consist of molecules which are made up of atoms.
(d) They form salts with metals in which the chloride, bromide or iodine ion ( ions) carries a charge of .
(e) They form molecular compounds with other non-metallic elements.
(f) In Group 7, the further the group the element is - the reactive the element; the its melting point and boiling point.
(g) A reactive halogen can displace a reactive halogen from an aqueous solution of its salt.

Q7(a) The elements in Group 0 are called the .
(b) They are all chemically very gases and exist as atoms rather than as gases like other gaseous elements such as oxygen or .
(c) They are used as gases in filament lamps and in electrical discharge tubes.
(d) The first element in the Group, helium, is much dense than air and is used in .

Q8(a) More than three-quarters of the elements of the periodic table are .
(b) They are mainly found in the hand columns (Group and Group ) and in the central blocks.

Q9(a) In the middle of the Periodic Table are horizontal blocks called the which are typically strong, , and have melting and points and .
(b) The metals or their compounds can act as and many of their compounds are highly .
(c) All are solid at room temperature and pressure except which is a .
(d) They are good conductors of and electricity.

Q10(a) About one quarter of the elements are non-metals and these can be gases, liquids or .
(b) The solids tend to be in appearance and are poor conductors of and electricity.
(c) The boiling points and melting points and densities tend to be relatively Bottom of Form