A. Chlorine is the most electronegative element out of the possible choices. Generally (though not 100% of the time) electronegativity increases as you go further left and up the periodic table.
Answer:
Oxygen
Explanation:
because oxygen is used when making and sustaining a fire.
I think this seems like something is missing from the question
I would say you should use or test it once a week to ensure it is working properly in an active laboratory since it is a workplace with significant chemical hazards so it would give peace of mind to know on a quite regular basis that it can be relied on in case of an emergency like an eye flush for example.
