Question 3(multiple choice worth 2 points)

a 20 gram piece of metal is added to a sample of 100 grams of water inside a calorimeter. if the metal is at a temperature of -5° celsius and the water is at 20° celsius, which of the following best describes what will occur inside the calorimeter?

the final temperature of the water will be 15° celsius.
the energy gained by the metal equals the energy lost by the water.
the final temperature of the water will be higher than the initial temperature.
the temperature lost by the water will equal the temperature gained by the metal.

The energy gained by the metal equals the energy lost by the water...
It is phrased this way because the focus is on the energy entering the system, more than it leaving the surroundings.

Matter- occupies space and possesses rest massno matter is the opposite

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant.