Question

the dog in the gif above is wearing boots! while this may look silly and cute, boots like this can protect dogs feet from cuts and burns.
a big concern for dog owners is making sure their pets are safe as the temperature of the pavement begins to rise. on a hot, sunny day the temperature of the sidewalk can get as high as 125°f (52°c). this can cause pain and burns to a dogs paws. table 1 below shows the relationship between air temperature and the temperature reached by different surfaces.
students calculations are below
q = mcδt
q = (1000 g)(0.840 j/g°c)(52°c - 51.6°c)
q = (1000 g)(0.840 j/g°c)(0.4°c)
q = 336 j
q = mcδt
q = (50 g)(1.2 j/g°c)(22°c - 29°c)
q = (50 g)(1.2 j/g°c)(-7°c)
q = -420 j
the student was expecting the thermal energy lost from the brick to be equal to the thermal energy gained by the boot. however, the values were not exactly equal. this is because the investigation:
o was not performed in a perfectly closed system. some thermal energy was transferred from the surroundings because systems always evolve toward less stable states.
o was performed in a perfecty closed system. some thermal energy was destroyed because systems always follow the law of conservation of energy
o was performed in a perfectly closed system. some thermal energy was created because systems always follow the law of conservation of energy
o was not performed in a perfectly closed system. some thermal energy was transferred to the surroundings because systems always evolve toward more stable states

Explanation:

Step1: Analyze the law of conservation of energy

In a perfectly closed system, energy is conserved. But in real - world experiments (like this one), systems are not perfectly closed.

Step2: Consider energy transfer

Thermal energy can be transferred to or from the surroundings. If the thermal energy lost from the brick is not equal to the thermal energy gained by the boot, it is likely because the system is not perfectly closed. Energy could have been transferred to the surroundings. Systems tend to evolve towards more stable states (in terms of energy distribution), and in non - closed systems, energy exchange with the environment is possible.

Answer:

was not performed in a perfectly closed system. Some thermal energy was transferred to the surroundings because systems always evolve toward more stable states.