Our Chemistry Project

Aluminium Aluminium FactsFacts• silvery-white chemical• lightest structure• corrosion resistant,

heat reflective, excellent conductor of electricity

• exceptional resistance to weathering and corrosion

• Used for storage tanks and highway signs

• easily recycled using less than 5% of the energy required to produced

• virgin aluminium• it is very light

PropertiesProperties of Aluminium• Symbol: AlSymbol: Al• Atomic number: Atomic number:

1313• Atomic Weight: Atomic Weight:

26.981526.9815• Group in period Group in period

table: 111Atable: 111A

• Density at 0 Density at 0 degree Celsius: degree Celsius: 2.6992.699

• Boiling point: Boiling point: 2467 degree 2467 degree CelsiusCelsius

• Melting point: Melting point: 660.37 degree 660.37 degree CelsiusCelsius

ApparatusApparatus• Aluminium Foil Aluminium Foil • Hydrochloric Hydrochloric

Acid (dilute)Acid (dilute)• Copper Sulphate Copper Sulphate

(powder form)(powder form)• Weighing Weighing

machinemachine• BeakersBeakers

•Test TubesTest Tubes

•Filter funnelFilter funnel

•BuretteBurette

•Stop WatchesStop Watches

•Filter PaperFilter Paper

•Distilled WaterDistilled Water

kept the same• Amount of hydrochloric acid Amount of hydrochloric acid

(5cm³, 0.5mol/dm³)(5cm³, 0.5mol/dm³)

• Pieces of aluminium foil Pieces of aluminium foil (1)(1)

• Temperature Temperature (room temp.)(room temp.)

changedchanged•Amount of copper sulphateAmount of copper sulphate

• Burette 5cm³ of HCl into the beaker Burette 5cm³ of HCl into the beaker and add in the aluminium foiland add in the aluminium foil

• Observation: the reaction between Observation: the reaction between HCl and Al is very slow and cannot HCl and Al is very slow and cannot be seen. Thus, copper sulphate, (a be seen. Thus, copper sulphate, (a transition metal compound) is used transition metal compound) is used to speed up the process. to speed up the process.

• Burette 5cm³ of HCl into the beaker and add in 0.5g of copper sulphate and shake the mixture.

• Put in the aluminium foil into the copper sulphate solution as we start the stop watch.

• Observe the reaction between the metal and acid.

• Record the time taken for the bubbles produced to subside.

• Observations: the aluminium foil immediately starts to decompose/rust. A hissing sound is heard due to the bubbles produced. Heat energy is also produced. The gas produced is hydrogen because

• Metal + Acid ---> Salt + HydrogenMetal + Acid ---> Salt + Hydrogen

1 1.5 3 3.5 5 10 20

6min31s 4min16s 3min37s 3min5s 2min54s 3min1s 8min23s

5min56s 3min25s 3min23s 3min 3min28s 3min15s 6min15s

3min53s 4min3s

Amt. Of Copper Sulphate (g)

5min 20s 3min54s 3min30s 3min3s 3min11s 3min10s 7min19s

• We have discovered that We have discovered that

~ If we add ~ If we add distilled waterdistilled water into the mixture, it into the mixture, it slows down the reaction process. slows down the reaction process.

~ If the amount of ~ If the amount of HCl HCl increases, the reaction increases, the reaction process is speeded up.process is speeded up.

•We have found out that the limiting We have found out that the limiting factor for this experiment is Hydrochloric factor for this experiment is Hydrochloric acid.acid.

As we increase the amount of As we increase the amount of copper sulphate, the rate of reaction copper sulphate, the rate of reaction between hydrochloric acid and between hydrochloric acid and aluminium speeds up too. Thus, more aluminium speeds up too. Thus, more bubbles are produced, more hissing bubbles are produced, more hissing sound is heard and more heat is sound is heard and more heat is produced too.produced too.

•Compton’s Encyclopedia Compton’s Encyclopedia CD-ROMCD-ROM