Question

a. Give one safety hazard when using the Bunsen burner and one precautionary to avoid this hazard.
b. What safety measures do you need to practice when using the oven to dry the solid product?

Answer 1

Answer (a) HAZARDS:

Physical – Risk of personal injury due to burns

Specimens/cultures – Risk of infection due to aerosols

Some risk of injury exists however the following actions/safety precautions should eliminate or reduce risks to an acceptable level.

SAFETY PRECAUTIONS Always turn off the Bunsen when not in use. NEVER leave a lit Bunsen unattended. Ensure that Bunsen is left on pilot light only and that the aperture is fully open so a yellow flame is visible. Ensure that the Bunsen is not obstructed prior to being lit i.e. it is not situated under a shelf. Ensure that no pieces of paper are stuck to shelves near to where Bunsen is situated Ensure no flammable liquids are placed near to a Bunsen burner.

Answer (b) Ectrically heated ovens are commonly used in the laboratory to remove water or other solvents from chemical samples and to dry laboratory glassware before its use. With the exception of vacuum drying ovens, these ovens rarely have any provision for preventing the discharge of the substances volatilized in them into the laboratory atmosphere. Thus, it should be assumed that these substances will escape into the laboratory atmosphere and could also be present in concentrations sufficient to form explosive mixtures with the air inside the oven.

The drying rate of test samples will be affected by the moisture conditions and number of samples in the drying device. When wet samples are placed in the drying device with nearly dry samples, completion of the drying may be restarted