Amelia is doing an experiment in which she is going to burn various solid chemicals to see the
colors of flames they produce. For this laboratory
experiment, what types of safety precautions
should she take?
tie hair back
leave open flame unattended to get a drink
only burn the amount of chemicals as
directed by the lab procedure
put out the flame with water from the eyewash
station

tie hair back

only burn the amount of chemicals as

directed by the lab procedure

Explanation:

The correct safety precautions for Amelia to take from the options would be to tie her hair back and to only burn the amount of chemicals recommended by the lab procedure.

With her hair left flowing freely, Amelia runs the risk of the hair catching flame while trying to burn the chemicals according to the procedure. Hence, tying her hair up into one neat bunch will limit the risk of it catching fire while working in the lab.

Also, burning less or more than the amount of chemicals recommended by the procedure may be dangerous or hinder Amelia from getting the right result.

see earlier

the duration of a photographic flash is related to an rc time constant, which is 0.100 μs for a certain camera.