please help on this questions

Question

1.At what temperature was thermal equilibrium reached? How long did it take to arrive at this temperature?

2.How does the temperature change within the first 60 seconds of the experiment? Within the last 60 seconds?

3.For the following scenarios, predict whether the time taken to reach thermal equilibrium would increase or decrease. 

 

The thickness of the metal divider is doubled:

The metal divider is replaced by a glass divider of the same thickness:

The water in the left compartment begins at 100C instead of 70C:

Time (s)	(Left Compartment Temp (°C)	Right Compartment Temp (°C)
0	70	10
30	52	28
60	47	33
90	42	38
120	41	39
150	40	40
180	40	40

Answer 1

(1). Thermal equilibrium is reached at 40ºC and it took 150 seconds to reach equilibrium.

(2). In the first 60 s, the temperature changes at an average rate of 0.38º/s whereas in the final 60 s, the temperature changes much more slowly at an average rate of ~0.02º/s

(3). See answer by @Robert S.

Answer 2

Hello, Aseel,

If the thickness of the metal divider were doubled, the equilibrium would be delayed sue to the added time for heat to move through the metal.

If the metal were replaced by glass, the equilibrium would also be delayed, due to the lower specific heat of glass. It takes less heat to warm it to a set temperature and so it takes longer for the heat to be transferred.

I'm not sure about the case in which the temperature is higher, but would guess that equilibrium would be reached sooner since the initial driving force is greater. I'm unsure, however, whether this is offset by the increase of time it takes to move the extra energy.

Bob