Alchemy Unit Investigation II: Basic Building Materials Lesson 1: A New Language Lesson 2: Now You See It... Lesson 3: What Goes Around Lesson 4: Create

Alchemy Unit

Investigation II: Basic Building MaterialsLesson 1: A New Language Lesson 2: Now You See It . . . Lesson 3: What Goes AroundLesson 4: Create a TableLesson 5: Breaking the Code

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Alchemy Unit – Investigation II

Lesson 1:

A New Language


Unit 1 • Investigation II

© 2004 Key Curriculum Press.

ChemCatalyst

There are two bottles on a shelf in a chemistry lab. Both contain a shiny metal substance that resembles gold. Bottle A is labeled Au(s). Bottle B is labeled FeS2(s).

• Do you think both bottles contain gold? Why or why not?

• What do you think the symbols on the bottles mean?



The Big Question

• What do the chemical symbols tells us about the substance inside the bottle?



You will be able to:

• Make sense of chemical names and symbols.



• An element is a unique form of matter that serves as a building material for more complex matter.

• Elements cannot be broken apart into two different substances.

Notes



Activity

Purpose: The goal of this lesson is to give you practice making sense of some of the “language” of chemistry, and translating chemical names and formulas.

(cont.)



Name Chemical formula

Description

Vial 1

Vial 2 copper nitrate

Vial 3 blue-green crystals

Vial 4

Vial 5 NaNO3(s)

Vial 6

Vial 7

Vial 8

Vial 9 nitric acid



Name Chemical formula

Description

Vial 10 fine, brown powder

Vial 11 NaOH(aq)

Vial 12

Vial 13

Vial 14 clear liquid

Vial 15 zinc sulfate

Vial 16

Vial 17 Cu(NO3)2(aq)

Vial 18



Making Sense

• When you turned the penny silver on the first day of class, you used zinc, Zn(s), and sodium hydroxide, NaOH(aq). Do you think the penny was coated with silver, Ag(s)? Explain your reasoning.



• A chemical formula is the set of symbols a chemist uses to represent a compound. Carbon dioxide is a compound. Its chemical formula is CO2.

• A compound is a substance that consists of two or more elements chemically combined together.

Notes

(cont.)



• A substance is aqueous if it is dissolved in water.

• The substance that is dissolved with water is called the solute.

• The water is referred to as the solvent.

Notes (cont.)



Check-In

• Imagine you find a vial that is labeled Na2SO4(aq). What does the label tell you about what is in this flask?



Wrap-Up

• Chemical symbols represent the elements that combine to form various substances. Each element has either a one or two letter symbol. The first letter is always capitalized, the second letter is always lower case.

• The chemical formula of a substance tells us what elements are in it as well as the relative amounts of each element in that substance.


Lesson 2:

Now You See It . . .




ChemCatalyst

• What is the starting ingredient you will be using in this lab?

• Why must part of the lab be done in a fume hood?

• When you filter, will you keep the solid or the liquid?



The Big Question

• What happens to copper once it has been mixed with other substances?




• Follow a procedure for a series of lab experiments and make observations.



Activity

Purpose: In this lesson you will complete a formal laboratory procedure. You will begin with copper powder and take it through a series of chemical steps, carefully observing and recording what happens at each stage. The goal is to figure out what happened to the original copper.

(cont.)



• You will not be allowed to begin the experiment until you can answer the questions about the lab correctly.

(cont.)

(cont.)



Setup and Safety Precautions:

This lab is safe, as long as each step is done carefully and correctly. Here are some safety guidelines.

• Everyone will wear safety goggles at all times.

• Be very careful handling the nitric acid, as it will burn any exposed skin. If some gets on your skin, wash the area immediately with water and inform your teacher.

(cont.)

(cont.)



• As you add the nitric acid to the copper, nitrogen dioxide, NO2(g), a poisonous gas, will be produced. Be careful not to breathe this gas. Use the fume hood when you add the nitric acid to the copper.

• Always be careful when heating chemicals—they will burn exposed skin more quickly when hot. When using the hot plate, make sure to set it at a medium setting (e.g. setting 4 out of 10). Be especially careful not to splash when stirring the chemicals.

(cont.)

(cont.)



• Sulfuric acid is an extremely strong acid, although you are using it here in a fairly dilute (unconcentrated) form. If you get it on your skin, wash it off with plenty of water, and inform your teacher.

(cont.)



What you added or did What you observed

Got copper powder from teacher

(cont.)



Making SenseExperimental stage Observations

1. Copper at the start Brownish, copper-colored, fine solid.

2. After adding nitric acid (HNO3)

Turned sky blue – liquid. Brownish gas.

3. After adding water (H2O) Still a blue liquid.

4. After adding sodium hydroxide (NaOH)

Clumpy dark blue.

5. After heating Turned black. Black solid in clear liquid.*

6. After adding sulfuric acid (H2SO4)

Clear blue solution.

7. After adding zinc (Zn) Bubbled. Chunks of solid appeared.

8. Final Zinc turned black and disappeared.



Check-In

• No Check-In



Wrap-Up

• No Wrap-Up


Lesson 3:

What Goes Around




ChemCatalyst

• What do you think happened to the copper powder in the copper cycle experiment when it was mixed with the nitric acid?



The Big Question

• What happened to the copper?




• Use your observations to draw conclusions and summarize them in a lab report.



“Nitric acid is added to solid copper powder, resulting in a blue solution and a brown gas.”

HNO3(aq) is added to Cu(s), resulting in

and .

Notes

(cont.)



HNO3(aq) is added to Cu(s), resulting in

Cu(NO3)2(aq) and NO2(g).

“Nitric acid is added to solid copper powder, resulting in a solution of copper nitrate and the

release of nitrogen dioxide gas.”

Notes (cont.)



Activity

Purpose: The goal of this activity is to use chemical symbols to keep track of an element when it goes through various chemical transformations.

(cont.)



removes H2O (water)

(cont.)

(cont.)



What you did

Chemical added

Write the chemical formula

What you saw

Your observations from the lab

Write the chemical formula and name

of the copper compound at each

stage

Where is the copper?

Got a sample of copper

Cu(s)

orangish-brown fine

powder

Cu(s)

solid copper powder

The copper is in the beaker because the teacher put it there.

Added nitric acid HNO3(aq)

Added sodium hydroxide

Added heat (removes H2O)

none

Added sulfuric acid

Added zinc Cu(s)

solid copper powder



Making Sense

• How would you describe what happened to the copper throughout this experiment?



• An element is a unique form of matter

that serves as a building material for more complex matter.

• Elements cannot be broken apart into two different substances.

• When elements are combined under ordinary conditions, the elements are not destroyed.

Notes (cont.)



Check-In

Sodium chloride, NaCl(aq), is added to silver nitrate, AgNO3(aq), resulting in NaNO3(aq) and a white solid. Identify the white solid from the list below.

A) AgCl(s)

B) AgCl(aq)

C) AgNO3(s)

D) NaCl(s)



Wrap-Up

• Elemental copper can be transformed through chemical reactions, and then recovered again.

• We can represent elements with symbols and keep track of them during chemical reactions.

• Elements combine and recombine but they are not destroyed in chemical reactions.


Lesson 4:

Create a Table




ChemCatalyst

In 1889 a Russian chemistry teacher created an organized table of the elements. At the time only 63 different elements were known. Below is a reproduction of that table.

• What do you think the numbers represent?

(cont.)





The Big Question

• How did Mendeleyev organize the elements?




• Explain how the periodic table of elements is organized.



• Dimitri Mendeleyev is credited with organizing the elements into the first periodic table.

• The main properties that Mendeleyev used to sort the elements were reactivity with one another and a number describing the atomic weight of each element.

Notes



Activity

Purpose: The goal of this lesson is to acquaint you with Mendeleyev’s organization of the elements by allowing you to create your own table from the patterns you see in the elements.



Making Sense

Below are five possible cards for the

element germanium. Where does

germanium belong in the table? Which

card seems most accurate to you? What

is your reasoning?

(cont.)



Germanium

Ge62.7

Germanium

Ge62.7

Germanium

Ge66.0

Germanium

Ge72.6

A B C

D E

Germanium

Ge72.6

(cont.)



• What would you add to the three empty

corners to complete the card?

Germanium

Ge

(cont.)

(cont.)



Completed Table(cont.)



Check-In

• Which of the following elements would you find in the same group on the periodic table? Explain your thinking.

CadmiumCd

Moderately soft, silvery solid, metal

React very slowly with water

Found inCdCl2 (s)

ZincZn

Moderately hard, silvery solid, metal

Reacts very slowly with water

Found in ZnCl2 (s)

IodineI

Purple solid, nonmetal

Reacts slowly with metals

Found inICl (s)

MercuryHg

Silvery liquid, metal

Does not react with water

Found inHgCl2 (s)



Wrap-Up

• Mendeleyev organized the periodic table based on the properties of the elements.

• Mendeleyev’s arrangement of the elements helped to predict the existence of undiscovered elements.


Lesson 5:

Breaking the Code




ChemCatalyst

• Where did Mendeleyev place copper, Cu, on the periodic table he created? (Note: The atomic weight of copper is 63.)

• Where would you put copper, Cu, on your periodic table? Explain your thinking.



The Big Question

• How can you predict properties of elements using a periodic table?




• Interpret some of the information given in the periodic table.



Notes

(cont.)



Notes (cont.)

(cont.)



Notes (cont.)

(cont.)



• The elements in the middle of the table are referred to as the transition elements, or the transition metals.

Notes (cont.)



Activity

Purpose: This lesson will help to identify many of the patterns that are contained in the periodic table of the elements.

(cont.)



(cont.)



Making Sense

• The elements copper and gold are both relatively unreactive. It is easy to bend and shape both metals. Both are used to make coins and jewelry. Is the similarity in their properties consistent with their locations on the periodic table? Explain why or why not.



Notes



Check-In

• Use the cards for Cu, copper, and Au, gold, to describe all you can about the element silver, Ag.

shiny, yellowmetal

found inAuCl

notvery reactive

Copper shiny, reddishmetal

found inCuCl

reactsslowly in air

Gold

Cu63.5

Au197.0



Wrap-Up

• Elements in each column of the periodic table have similar properties.

• We can predict the characteristics of a missing element based on the qualities of the elements found adjacent to it in a periodic table.

Documents

Alchemy Unit Investigation II: Basic Building Materials Lesson 1: A New Language Lesson 2: Now You See It... Lesson 3: What Goes Around Lesson 4: Create