Answer:
B) a substance's color and odor changed Explanation: A signal that a chemical change has occurred is when its odor (its smell) or its appearance has changed.
The answer is number 4 or the exchange of energy with the surroundings. Calorimetry is a measurement of energy that is formed or absorbed in a certain process. The calorimeter is the instrument used in order to measure the energy. It is recommended that a calorimeter should be a closed system so as to measure precisely the energy and avoid or lessen the exchange of energy with the surroundings. Thus, comparing an open ceramic mug and an insulated mug with a lid, the greatest difference is the energy lost to the surroundings.
Answer:
the answer for this question is the option D
Answer: The density of chloroform is 1.47 g/mL
Explanation : Given,
Volume = 40.5 mL
Mass of cylinder = 85.16 g
Mass of cylinder and liquid = 145.10 g
First we have to calculate the mass of liquid (chloroform).
Mass of liquid = Mass of cylinder and liquid - Mass of cylinder
Mass of liquid = 145.10 g - 85.6 g
Mass of liquid = 59.5 g
Now we have to calculate the density of liquid (chloroform).
Formula used:
Now putting g all the given values in this formula, we get:
Therefore, the density of chloroform is 1.47 g/mL
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