risk assessments: example of risk, the way to reduce risk

Testing for metal ions with sodium hydroxide solution

Sodium hydroxide solutioms with conc of 0.5 or higher are corrosive and extremely dangerous to eyes

Wear eye protection, use conc below 0.5

Testing organic compounds by heating with acidified potassium dichromate (VI)

Many organic molecules are flammable

Heat with water bath instead of Bunsen burner

Nitration of benzene

Benzene is a carcinogen

Use a different aromatic compound with a low hazard (methylbenzene)

Testing solid halides with concentrated sulfuric acid

Concentrated sulfuric acid is very corrosive

Wear gloves

Testing reaction kinetics in sodium thiosulfate and acid reactions

Toxic sulfur dioxide gas is produced

Do the experiment in a fume cupboard, and/or do the experiment on a very small scale to minimise the amount of gas formed