Alchemy Unit Investigation V: Building with Matter · Rules for Salty Eights: The point of the game is to make compounds and to be the first to play all of the cards in your hand

Alchemy Unit

Investigation V:

Building with Matter

Lesson 1: You Light Up My Life

Lesson 2: Electron Glue

Lesson 3: Nobel Gas Envy

Lesson 4: Getting Connected

Lesson 5: Salty Eights

Alchemy Unit – Investigation V

Lesson 1:

You Light Up My Life

© 2004 Key Curriculum Press.

Unit 1 • Investigation V

ChemCatalyst

• If you were to drop a spoonful of salt,

NaCl, into a glass of water, what would

happen? If you were to drop a gold

ring into a glass of water, what would

happen?

• What do you think is different about the

atoms of these two substances? Why

wouldn’t the individual gold atoms

come apart?



The Big Question

• What patterns do we see in the

properties of substances?



You will be able to:

• Predict whether MgSO4(aq), epsom

salts, will conduct electricity.





Activity

Purpose: This lesson allows you to

collect evidence regarding some of the

properties of substances, and look for

patterns.

(cont.)



Predictions Test Results

Substances Conduct?

Yes/No

Dissolve?

Yes/No

Conduct?

Yes/No

Dissolve?

Yes/No

H2O(l), water Yes

Al(s), foil aluminum

C12H22O11(s), sucrose

(sugar)

NaCl(s), salt,

sodium chloride

SiO2(s), sand,

silicon dioxide

C20H42(s), paraffin (wax)

C2H6O(l), ethanol

Cu(s), copper

CaCl2(s),

calcium chloride

CuSO4(s), copper

sulfate



(cont.)

(cont.)



Substances that dissolve in water

Conduct Don’t conduct

(cont.)



Making Sense

• If it is dangerous to take a bath with a

blow dryer, what must also be true

about the water in the bathtub?



NaCl – salt

CuCl2 – calcium

chloride

CuSO4 – copper

sulfate

H2O – water

C12H22O11 –

sugar

C2H6O – ethanol

Au – gold

Cu – copper

Al – aluminum

SiO2 – sand

C20H42 – paraffin

Dissolves

Yes No

Conducts

Yes Yes No No

Conducts

Notes



Check-In

• Predict whether MgSO4(aq), epsom

salts, will conduct electricity. State your

reasoning.



Wrap-Up

• Not all substances conduct electricity.

• Substances that do conduct electricity

involve either solid metals, or metal-

nonmetal compounds dissolved in

water.

• Not all substances dissolve in water.


Lesson 2:

Electron Glue



ChemCatalyst

A gold ring is made up of individual gold

atoms.

• What keeps the atoms together?

• Why don’t the atoms just fall apart from

each other?

• What parts of the atom do you think

are responsible for keeping the atoms

together in a solid?



The Big Question

• How can we use bonding to explain

the properties of substances we

encounter?




• Classify the bonding that occurs in the

making of brass.



• A chemical bond is an attraction

between atoms that holds them

together in space.

Notes



Activity

Purpose: This lesson helps to explain

the physical properties of basic

substances by examining the types of

bonds that exist between the atoms of

these substances.

(cont.)



Ionic Covalent

Network Metallic Molecular

Covalent

(cont.)

(cont.)



Ionic Covalent Network

Metallic Molecular Covalent

(cont.)



Making Sense

• If you have the chemical formula of a

substance, how and what can you

figure out about it’s properties?

Explain. Use the compound silver

nitrate, AgNO3, as an example.



Model 1: IONIC

Properties:

Made of metal and non-metal atoms

Dissolves in water

Conducts electricity when dissolved but not when

solid

Brittle solids

Description of drawing: Spheres without gray

areas represent metal atoms. Spheres with gray

areas are non-metal atoms. Metal atoms “give up”

their valence electrons to non-metal atoms.

Notes

(cont.)



Model 2: COVALENT NETWORK

Properties:

Made entirely of nonmetal atoms

Does not dissolve in water

Does not conduct electricity

Very hard solids

Description of drawing: Valence electrons

connect atoms with each other in all directions

– like a grid or network.

(cont.)

Notes (cont.)



Model 3: METALLIC

Properties:

Made entirely of metal atoms

Do not dissolve in water

Conduct electricity

Bendable solids


are free to move throughout the substance like

a “sea” of electrons. (cont.)

Notes (cont.)



Model 4: MOLECULAR COVALENT

Properties:

Made of nonmetal atoms

Some dissolve in water, some do not

Do not conduct electricity

Tend to be liquids or gases or softer solids


are shared between some atoms. This creates

small stable units within the substance.

(cont.)

Notes (cont.)



• Atoms which are connected into many

identical units are called molecules.

They units may be composed of only

two atoms or of dozens of atoms.

(cont.)

Notes (cont.)



NaCl – salt

CuCl2 – calcium

chloride

CuSO4 – copper

sulfate

H2O – water

C12H22O11 –

sugar

C2H6O – ethanol

Au – gold

Cu – copper

Al – aluminum

SiO2 – sand

C20H42 – paraffin

Dissolves

Yes No

Conducts

Yes Yes No No

Conducts

Ionic Molecular

Covalent

Metallic Covalent

Network

Notes (cont.)



Metal

atoms

Non-Metal

atoms

Metal &

Non-Metal

atoms

Metallic Covalent

Network

Molecular

Covalent Ionic

Notes (cont.)



Check-In

• On the very first day of class, you

combined copper with zinc to form

brass. How would you classify the

bonding in brass? Explain.



Wrap-Up

• A chemical bond is an attraction

between atoms involving the valence

electrons.

• There are four types of bonds: ionic,

extended covalent, molecular covalent,

and metallic.


Lesson 3:

Noble Gas Envy



ChemCatalyst

• What type of bonding does this picture

represent?

• What happens to the charge on each

atom?



The Big Question

• What ion charges are formed when

atoms attain a noble gas electron

configuration?




• Predict what would have to happen for

potassium to obtain a noble gas

configuration.



Notes



Activity

Purpose: You will explore the ions that

are formed when atoms give up and

receive electrons from other atoms.



Making Sense

• Why do you think the noble gas

configuration is especially stable?



• A valuable piece of information that

can help us predict which ions might

be encountered in chemistry: Atoms

tend to lose or gain electrons to

attain the electron configuration of

the noble gas nearest to it on the

periodic table.

Notes

(cont.)



• Atoms with a positive charge are called

cations.

• Atoms with a negative charge are

called anions.

(cont.)



Check-In

• Write the electron configuration for

potassium, K.

• What would have to happen for

potassium to have a noble gas

configuration? Explain.



Wrap-Up

• Noble gases are stable with filled

outermost electron shells.

• Atoms can gain or lose electrons to

end up with a noble gas configuration.

• When atoms lose electrons, they have

a positive charge and are called

cations.

• When atoms gain electrons, they have

a negative charge and are called

anions.


Lesson 4:

Getting Connected



ChemCatalyst

• Only certain combinations of elements

result in the formation of compounds.

Li, lithium, will react with F, fluorine, to

form LiF, but it won’t form LiF2 or LiF3.

Mg, magnesium will react with F to

form MgF2, but it won’t form MgF or

MgF3. Explain what you think is going

on.



The Big Question

• What determines how two elements

will combine to form ionic compounds?




• Use the number of valence electrons

to determine which ionic compounds

can form.



Activity

Element 1

(metal)

# of valence

electrons

Element 2

(nonmetal)

# of valence

electrons

compound total # of valence

electrons

Na 1 F 7 NaF

sodium

fluoride

8

Mg O MgO

magnesium

oxide

Mg 2 Cl 7 MgCl2

magnesium

chloride

16

Ne Ne

neon

Be F BeF2

beryllium

fluoride



Element 1

(metal)

# of valence

electrons

Element 2

(nonmetal)

# of valence

electrons

compound total # of valence

electrons

MgS

magnesium

sulfide

CaCl2

calcium

chloride

Na Br

K Se

Al N

Al O Al2O3

aluminum

oxide

Al F



Making Sense

• Can you make a rule that helps you predict the composition of compounds that form?



• Rule of Eight: Ionic compounds tend

to form from atoms that together have

a total of 8 (or a multiple of 8) electrons

in their outermost (valence) shells.

This gives each ion a valence electron

configuration identical to a noble gas

and makes them very stable.

Notes



Check-In

• What elements will combine with Sr,

strontium, in a one-to-one ratio?



Wrap-Up

• Elements react to form compounds in

such a way as to result in 8 electrons in

their outermost (valence) shell (or a

multiple of eight).

• Compounds with eight valence electrons

are very stable.

• Noble gases already have eight valence

electrons and don’t combine with other

elements to make new compounds. They

are already very stable.


Lesson 5:

Salty Eights



ChemCatalyst

• List the compounds you can make with

pairs of cards of two different elements.

• List the compounds you can make with

three cards and only two different

elements.



The Big Question

• What salts can be formed by

combining a metal and a non-metal?




• Apply the octet rule.



Activity

Rules for Salty Eights:

The point of the game is to make

compounds and to be the first to play all

of the cards in your hand. These

compounds can have two or three or

more cards in them, but they can only

have two different elements. The game

ends when a player uses up all of the

cards in his or her hand making

compounds. (cont.)



• Shuffle the deck as best as possible.

• Deal eight cards to each player.

• The player to the left of the dealer plays first.

• Using at least two cards from your hand, try

to make one compound – the valence

electrons must add up to eight or a multiple

of eight. You must have at least one pink

card and one blue card with each compound

(the noble gases—green cards—are an

exception and can be played singly). (cont.)

(cont.)



• You must play every turn. In other words

you must make one compound each time

it is your turn. If you cannot make a

compound you must draw from the draw

pile until you can put down a compound.

• When you form a compound during your

turn simply place those cards on the

table in front of you. As soon as you put

down a compound you must name it and

then your turn is over. (cont.)

(cont.)



• Play proceeds around the circle until a

player uses up all of his or her cards.

• A player gets 20 points for going out

first.

• Wild cards can be used as any element

in that particular group (Wild cards only

exist for Groups 1 and 7). The player

must identify which element a wild card

represents at the time it is played. (cont.)

(cont.)



Scoring:

Every compound played on the table is

worth points. The cards left in a person’s

hand are subtracted.

• 5 points for every noble gas.

• 10 points for every compound made

out of two cards.


out of three cards. (cont.)

(cont.)




out of four cards.


out of five cards.

• 20 points for going out first.

Any player with cards left in his or her

hand must count up the number of

valence electrons and subtract them from

his or her total. (cont.)

(cont.)



Metal Nonmetal Compound

Formula

Compound Name Point

value

Total



Check-In

Which of the following compounds are

likely to form?

(a) Na2S

(b) K2Mg

(c) AlBr2

(d) Na3N

(e) OCl

(f) CaMgO2



Wrap-Up

• Ionic compounds tend to form from

atoms that together have a total of 8 (or

a multiple of 8) electrons in their

outermost (valence) shells

• Compounds with eight valence electrons

are highly stable.

• Noble gases already have eight valence

electrons and don’t combine with other

elements to make new compounds. They

are already highly stable.


Lesson 6:

As Good as Gold



ChemCatalyst

• Name three items that might be on an

exam covering the entire Alchemy

Unit.



The Big Question

• Can an element be turned into

something else?




• Explain the relationship between

compounds, atoms, elements, and the

periodic table.



Activity

Purpose: This lesson provides you with

end-of the-unit review and practice.

(cont.)



Element

Symbol

Atomic

No.

Group

No.

# of

protons

Number of valence electrons

Electron

configuration

oxygen

iodine

iron

radon

tungsten

lead

(cont.)

(cont.)



Substance Conducts?

Yes/No

Dissolves in

H2O?

Yes/No

Conducts

after

dissolving?

Type of

bonding

CuxZnx – brass

CSi – silicon

carbide

C3H8 – propane

CuCl2 – copper

chloride

(cont.)



Making Sense

It is not possible to convert copper into

gold in chemical reactions. This can only

be done by nuclear reactions, which

require the energy of a supernova. Thus,

we must resort to using chemistry to

create things that are as good as gold.



a) Investigation I: How do the mass and

volume of copper and gold compare?

b) Investigation II: Copper and gold have

similar properties, but gold is more

bendable than copper. Is this consistent

with their locations on the periodic table?

c) Investigation III: How are copper atoms

different from gold atoms? Be specific

about the difference in the numbers of

atomic particles. (cont.)

Notes (cont.)



d) Investigation V: The golden penny

produced on the first day of this Unit was

brass, CuZn. If you wanted to make a

substance that is as good as gold, would

you choose any elements on the right

side of the periodic table? Why or why

not?

Notes (cont.)



Check-In

• No Check-In.



Wrap-Up

• No Wrap-Up.

Documents

Alchemy Unit Investigation V: Building with Matter · Rules for Salty Eights: The point of the game is to make compounds and to be the first to play all of the cards in your hand