I am not sure what sort of thermometers you have in your klab but a Mercury-in-glass thermometer should be fine up to 350 deg C. Thermometers based on thermocouples can go very much higher. So the simple answer is that nothing happens.
In a mercury thermometer, the level of mercury falls as the temperature of the air around it cools.A mercury thermometer has a bulb of mercury at the bottom and a thin tube above it with markings in Celsius degrees or Fahrenheit degrees. When the temperature warms, the mercury expands and rises up the tube. When the temperature cools, the mercury contracts and shrinks back toward the bulb at the bottom.
the temperature rises and the thermometer breaks releasing mercury
it expands
it expands
it expands
Nothing will happen, except the thermometer will show the fridge's interior temperature.
They expand causing them to move in the only direction available, up the thermometer.
Depending on the intensity of the light the thermometer should indicate an increase in temperature.
It contracts.
mercury explodes
They Increase.
the termometre gets warmer