In a medical thermometer, mercury warmed up by 2 ° C, receiving 0.56 J of heat.

In a medical thermometer, mercury warmed up by 2 ° C, receiving 0.56 J of heat. How much mercury is in a thermometer if its heat capacity = 140 J / (kg • ° С)?

Initial data: Δt (change in temperature of mercury) = 2 ºС; Q (the amount of heat that mercury received) = 0.56 J.

Reference data: according to condition С (specific heat of mercury) = 140 J / (kg * ºС).

The mass of mercury in a thermometer can be determined from the formula: Q = C * m * Δt, whence m = Q / (C * Δt).

Let’s calculate: m = 0.56 / (140 * 2) = 0.002 kg or 2 g.

Answer: A medical thermometer contains 2 grams of mercury.