/ Name Class Date

L ab or at ory Ina esti gatiottChapter 6 Class i f icat ion of E lements: The Per iod ic Table 15Investigating the ActivitySeries of the MetalsBackground In formation

One r lay to arrange the clements in the periodic table is bv order of their act iv i t r , . Ametal is said to be more act ive tharr another metal i f i t u ' i l l replace the less acr ive metal I iomalsolut ion of one of i ts conrpounds. This can be observed beciuse the nretal rv i th the lorveract iv i ty is "plated out" as pure nretal on the piece of metal u ' i th the higher act iv iry. Byperforming a ser ies o[ experiments, ] 'ou can develop a l ist of nretals in order of their act iv i ty.

In this i rrvest igat ion ) 'ou wi l l test z inc, copper, and lead to see i f they' rv i l l replace eachother in solut ions of their compourrds. Using ,vour results, you can develop a short l ist inorde r of act iv in, .

Problem

FIou' can fou determine the relat ive act iv i t ies of z inc, copper, and lead?

Materials (per pair of students)

solut ionscopper sulfatelead acetatezinc sul fate

l0-crn str ipszincleadcopper

sandpaper9 smal l test tubcstest-tube racksafety gogglesmasking tape

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Procedure@ t. Put on salety gclggles.

2. Arrange the nine resr rubes in three groups of three each. Using smal l pieces of nraskingtape, label the f i rst r l r ree test tubes Lcad Acetate, the next three Zinc Sulfate, and thelast three Copper Sulfate. See Figure l .

Test-tube rack

Copper _--

sulfale solulionooe

' .: :' t

Figure 1

A g. f i t t rhe appropriatel l ' labcled rhree tubes one third ful l of lead acetate solut ion. Fi l l theappropriatelv labeled three tubes one third ful l of z inc sul [ate solut ion. Fi l l theappropriatelv labeled renraining three tubes one third ful l of copper sul fate solut ion.

4. Clean the metal strips bv rubbirrg n'ith sandpaper. Using a separate tube for each strip ofmetal , place srr ips of lead, zinc, and copper in each of the three kinds of solut ions.

1! 5. After several minutes, examine the strips flor cvidence of a reaction; remove them fromthe solutions if necessarv. Rccord 1'our obsen'ations irr the Data Table. Also note if thesolut ion changed color.

Observations

DATA TABLE

Lead Acetate Zinc Sulfate Copper Sullate

Lead

Zinc

Copper

l . Which metal did not react rv i th any of the soh-rt ions i t was placed in?

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2. Which metal reacted with all but its ou'n solution?

Class Date

Analysis and Conclusionsl. List the metals in order of decreasing act iv iry.

2. Hor.' could you tell which of rhe tlrree metals q'as the mosr active?

Crit ical Thinking and Applicationl. Magnesium is more active than zinc. Horv would a str ip of magnesium have reacted in rhe

three solutions you studied?

2. Tin is less act ive than zinc but rnore act ive than lead.How rvould a str ip of t in have

reacted in ' this invest igat ion?

3. A str ipof silver does not react with any of the solutions tested. What must be true about

si lver?

What ex

copper?

periment could you perform in order to determine if iron is more active than

5. I \ {etals l ike plat inum and gold are often said to be inact ive. What does this mean?

Going Further

l. Read about plating with copper or silver. How is plating done commercially? How couldyou do it in the laboratory?

2. Determine the act iv i ty of aluminum relat ive to the other metals.

4 .

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