Take Out

PencilAnnotated article

Catalyst1. What was Johann Döbereiner’s

contribution to chemistry in 1829?

2. Why is Dmitri Mendeleev considered the “Father of the Periodic Table”?

3. Why do you think the placement of H and He are considered “unresolved issues”?

Your task in class today, and to finish for class on Tuesday (2nd & 3rd periods) or Wednesday (4th & 5th periods) is to create a timeline of the history of the periodic table. You may use your reading packet, as well as any other information you find in books and online. The rubric must be attached to the front of your timeline before it will be accepted.

• Your Period Table Timeline must:

• Include at least 6 dates/time periods• Include a written description of the event next to the date/time

period• Include a visual representation next to each date/time period• Take up almost all space on an 8.5 x 11 sheet of printer paper

(you may use a larger piece of paper too)• Include a title• Include your full heading on the back

HomeworkComplete your Periodic Table Timeline and bring in to class, with rubric attached to the

front

If you have colored pencils, please bring them with you to class tomorrow

Take Out

Catalyst sheetPencilScience Notebook

Make a pile of timelines in center of table w/ rubric attached

Tape paper I give you onto page 48

CatalystComplete page 48 in science notebook with your group

On your Catalyst sheet, describe in detail the patterns that you see on page 48

Why isn’t the world made only of elements? How do the atoms of different elements combine to form molecules?

The answers to these questions are related to electrons and their energy levels. And the roadmap to

understanding how electrons determine the properties of elements is the periodic table.

Valence Electrons: The key to bondingYou have learned that electrons are contained

within energy levels. An atom’s valence electrons are those electrons

that are in the highest energy level and are held most loosely.

The number of valence electrons in an atom of an element determines many properties of

that element, including the ways in which the atom can bond with other atoms.

8 is the lucky number!!Most atoms are more stable – less likely to

react – when they have filled their outer most energy level OR if they have eight

valence electrons (their outer s & p orbitals are full).

In your notes, draw the electron dot diagrams of hydrogen, carbon, and oxygen.

How many more electrons are needed to make an oxygen atom stable? A hydrogen atom? A

carbon atom?

A row of elements across the periodic table is called a period. Hydrogen and helium make up the first period. Label the periods.

Elements in the same column are called a group or family. Label the groups of your periodic table.

Neon

How many valence electrons?

Argon

How many valence electrons?

Krypton

How many valence electrons?

Xenon

How many valence electrons?

A period ends when the highest energy level has eight electrons.

The elements within a group always have the same number of valence electrons, and for this reason, the elements within a

group have similar properties.

Why the name “noble gas”?Most atoms are more stable – less likely to

react – when they have eight valence electrons.

The other elements strive to be like this! They strive to be stable.

On your periodic table, color your noble gases orange.

When atoms react they usually do so in a way that makes each atom that is participating in

the bond more stable.

One of two things may happen:1.The number of valence electrons increases to

eight (or two in the case of hydrogen).2.The atom gives up its most loosely held

valence electron(s).

Homework

Complete page 52 in science notebook

Homework

Update Vocabulary using website

Study Vocabulary and Periodic Table notes for quiz on Friday

Take Out

Catalyst SheetPencilScience notebook open to homework

Catalyst1. Write down everything you

know about the Noble Gases. 2. Why is helium in group VIIIA

and considered a Noble Gas, even though it doesn’t have 8 valence electrons?

One of two things may happen:1. The number of valence electrons increases to eight (or two

in the case of hydrogen).2. The atom gives up its most loosely held valence electron(s).

What does oxygen need to become stable?

Atoms that react this way become chemically combined, or bonded

together. A chemical bond

is the force of attraction that

holds two atoms together as a result of the

rearrangement of valence electrons between them.

Look at the elements in the column just to the left of the noble gases. The elements in group VIIA are called the halogens. Atoms

in the halogen family have seven valence electrons. A gain of just one more electron gives these atoms the stable number of 8 electrons. As a result, elements in the halogen family react easily with other elements whose atoms can give up or share

electrons.

When iodine, a halogen, reacts with aluminum, a purple gas is produced

Bromine, a halogen, reacts vigorously with

hydrogen

http://www.youtube.com/watch?v=gFGwY_S4j_M

http://www.youtube.com/watch?v=R6bBs2D0cpA

At the far left side of the periodic table is Group IA,

called the alkali metal family. Atoms of the alkali metals

have only one valence electron. Therefore, alkali

atoms can become chemically more stable by

losing their one valence electron. This makes them

very reactive.Color the alkali metals yellow.

http://www.youtube.com/watch?v=fmOd8_ReNnQ

The alkaline earth metals are in Group IIA

The alkaline earth metals are silver

colored, soft metals, which react readily

with halogens to form ionic salts, and

with water, though not as rapidly as the alkali

metals, to form strong alkaline (basic) hy

droxides.Color the alkaline earth

metals red

http://www.youtube.com/watch?v=DFQPnHkQlZM

Reaction of magnesium with carbon dioxide

Dry Ice = the solid form of carbon dioxide

http://www.youtube.com/watch?v=wqErrNvns4o

Metals vs Non-MetalsMetals – Give up their valence electrons during

chemical bondingNon-Metals – Gain valence electrons during

chemical bonding

Color the transition metals purple

Take Out

CatalystPencilScience notebook open to Vocabulary

CatalystDescribe everything you know

about alkali metals and alkaline earth metals

CatalystDescribe the difference between a

metal and non-metal

Other metals polonium Very rare radioactive metal that is used as fuel in nuclear reactors; it emits

radiation that is much more powerful than that of uranium.bismuth Relatively rare metal that is used especially in alloys and cosmetics and in

medicine (treatments for gastric ulcers and diarrhea).lead Heavy toxic metal that is used to prevent corrosion, as a protection against

radiation and in accumulator batteries, paint and glass.thallium Metal that is used especially in infrared detectors and some kinds of glass.tin Metal that is used especially as an anticorrosive for copper and steel and

as a component in the preparation of bronze, welding and toothpaste.

indium Very rare metal that is used especially in race car engines and electronic

devices, and as a coating for glass.gallium Rare metal that is used especially in high-temperature thermometers,

electroluminescent diodes and television screens (the color green).aluminum Light metal that is used especially in aeronautics, cars, buildings, electric

cables, kitchen utensils and packaging.

Color the “Other Metals” brown

What happens when an atom loses or gains electrons?

An ion is formed

An ion is a charged atom or particle

Cation = a positively charged particle (electrons were lost)

Anion = a negatively charged particle (electrons were gained)

Ionic bond involves TRANSFER of electrons

Ionic Compounds

Several elements, known as metalloids lie along a zigzag line between the metals and the nonmetals. Depending on the

conditions, these elements can react as either metals or nonmetals. The metals have from 3 to 6 valence electrons and can either lose or share electrons when they combine

with other elements.Color these metalloids blue

The elements below are nonmetals, and have four or more valence electrons. Like the halogens, these nonmetals

become stable when they gain or share enough electrons to have a set of eight valence electrons.

Color these nonmetals green

Covalent bonds involve SHARING of electrons

Covalent Compounds

HydrogenHydrogen is considered to be a nonmetal. It is located above

Group 1 in the periodic table because it has only one valence electron. However, even though hydrogen is a reactive

element, its properties differ greatly from those of the alkali metals.

http://www.youtube.com/watch?v=fesgl5Cs5FY

Freefall

http://www.youtube.com/watch?v=dOoHArAzdug

Homework

Update Vocabulary

Study all Vocab and Periodic Table Notes for Quiz on Monday