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Human beings are one of the most defenselessanimals. We lack sharp teeth, claws, speed, etc.

What we do have is a superior brain. Make tools to compensate for what we dont have.

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Bones, animal teeth, stones, and wood are somematerials used.

It is believed that man first discovered goldand silver. They found these metals beautiful, but too soft to be

used for anything utilitarian (having a usefulfunction).

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About 10,000 years ago man discovered andused another metals- copper Soft- used for decorations

Around 3800 B.C- man discovered tin Useless in its raw form

Alloyed with Copper, a tough metal was created Metal Alloys are a mixture containing two or more

metallic or non-metallic elements usually fused

together when in a molten form.

Birth of the Bronze age.

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Eventually mankind discovered iron ore,and developed the techniques forextracted iron from that ore.

Iron age was born around the 12th

century B.C.Humans experimenting with ironforging techniques developed the firstiron alloy- steel.

Steel is an alloy between iron and carbon. Other metals are added to modern steel for

strength and higher melting point.

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How does the history of

the discovery of metalsrelate to chemistry?

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In the last unit you learned that the alkalimetals were the most reactive metals.

You also learned that most metals react with

acid.Some of you may have also noticed a reactionbetween your unknown samples and the CuCl2

What determines how and with what a metalreacts?

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One way to study the reactivity of metals is totest how they react with oxygen Oxygen is plentiful

Need for combustion.

Copper vs. Magnesium Demo

Compare this to gold.

Does Au tarnish easily?

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Rank the reactivity of Au, Cu, and Mg?

Which do you think will be used for jewelry,and for the wires and electrical contacts in

expensive electronic devices, and car air bags?

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Table on page 121 that ranks how reactive ametal is. Notice that Lithium is at the top of the list

Most reactive metal

Never found free in natureExtracted by expensive electrometallurgical extraction

Electricity passed though ore

Expensive to store: highly reactive with air

Gold is at the bottom of the list Least reactiveUsed in jewelry, sensitive electrical components, art

Can be found free in nature or in ore

Extracted by heating ore

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What determines how metals are found innature?

Reactivity More reactive metals found in ores.

Harder/ more difficult to process

Less reactive metals found free Easier to process

Refer to page 121 in textbook for Activity Series

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An activity series can be used to predictwhether or not a reaction will take place.

In you last lab Unknown G was Zn metal.

You all should have seen a reaction betweenthe Zn and the CuCl2 solution.

Look at Zn and Cu on the activity series table.

Notice Zn is above Cu on the table

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In general, atoms of a more reactive metal(higher on the table) will cause ions of a lessreactive metal to be converted to its metallic

form.Christmas Ornament Activity after ThanksgivingBreak (maybe?).

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Do you see the relationship between howreactive a metal is, and when it wasdiscovered by man?

Do you see the relationship between howreactive a metal is, and how difficult it isto extract?

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1. What trend in metallic reactivity to you see as yougo from left to tight across a period?

2. Where are the most reactive metals on the P.T.?

3.

Where are the least reactive metals found on theP.T.?

4. Will iron metal react with a Lead (II) nitratesolution? Explain.

5.

Will platinum metal react with the lead (II) nitratesolution? Explain.

6. Which are less expensive, more reactive or lessreactive metals? Why would reactivity influencethe price?

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1.

2.

3.

4.

5.

6.

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Finish Pre-lab

MUST BE DONE INNOTEBOOKS.Any pre-labs done onloose paper will losehalf of your points.