What is the correct position of the thermometer bulb when getting the temperature of a solution in a beaker?

Question

what is the correct position of the thermometer bulb when getting the temperature of a solution in a beaker?

a) thermometer bulb immersed in middle solution.

b) thermometer bulb touching bottom of beaker.

c) thermometer bulb touching sides og beaker.

Answer 1

Ideally you want the bulb of the thermometer to not touch the glass walls of the beaker, either the bottom or the the sides.  

But there is more that the question didn't ask.  Most common laboratory thermometers are 76mm immersion thermometers.  That means that to get an accurate reading that the bottom 76 mm or 3 inches should be immersed.  In fact, there's usually a line around the thermometer to indicate the immersion point.

Obviously, it may not be possible to immerse the thermometer that much.  Then hit some happy medium between the amount of immersion and keeping the bulb off the glass of the beaker.