Precaution.
- Experiment should be done in a fume cupboard or in the open.
Reason:
- Chlorine gas is poisonous and will thus be harmful to the human body.
Procedure:
- Dry chlorine gas is passed over iron wool as per the diagram.
Conditions.
Chlorine gas has to be dry (done by the anhydrous calcium chloride in the U-tube)
Reason:
To prevent hydration hence oxidation of iron (which will then form Fe
2O
3.
5H
2O) hence preventing reaction between iron and chlorine.
Iron metal must be hot; and this is done by heating.
Reason:
To provide activation energy i.e. the minimum kinetic energy which the reactants must have to form products.
- Anhydrous calcium chloride.
- In the U-tube; to dry the chlorine gas.
- In the thistle funnel; to prevent atmospheric water vapour (moisture) from getting into the apparatus and hence reacting with iron (III) chloride.
Observations:
- Iron metal glows red-hot.
- Red brown fumes (FeCl
3(g)) are formed in the combustion tube.
- A black solid (FeCl
3(s)) is collected in the flask.
Note:
- Iron (III) chloride cannot be easily collected in the combustion tube.
Reason:
- It sublimes when heated and hence the hotter combustion tube causes it to sublime and its vapour is collected on the cooler parts of the flask.
Kavungya answered the question on
April 29, 2019 at 09:15