How many atoms of mercury are in a light bulb?

Compact fluorescent light bulbs contain mercury. (For that reason, it is important to be very careful with a broken compact fluorescent bulb, because mercury is highly toxic.)
Most other kinds of light bulbs do not contain any significant amount of mercury.
Compact fluorescent light bulbs contain mercury. (For that reason, it is important to be very careful with a broken compact fluorescent bulb, because mercury is highly toxic.)
Most other kinds of light bulbs do not contain any significant amount of mercury.