This mathematical model describes the changes that occur in a sample of water as its temperature increases. Use this model to predict what will
happen to the motion of the molecules in a sample of water that is being
heated from 50° to 100°C.
200°C
vaporization
150°C
melting
100°C
Temperature (°C)
water vapor
50°C
liquid water
0°C-
--50°C
10
20
ice
30
Time (min)
40
50
60
70
O A. The motion will change very little.
O B. The molecules will stop moving.
O C. The movement of the molecules will gradually decrease.
O D. The movement of the molecules will gradually increase.

The correct answer is D. The movement of the molecules will gradually increase.

Explanation:

At the beginning of the model the state of matter of the water is solid, in this, particles have a defined arrangement and are together, which stops particles from moving freely and only allows them to vibrate. However, as the substance is heated the thermal energy (heat) increases in the sample, this causes particles to move more and the arrangement of it changes. Due to this, when the ice melts and there is liquid water particles move more than in solid states, which makes ice lacks a defined shape. Moreover, as the heat continues to increase the thermal and kinetic energy (movement) increases, indeed in gas state (water vapor) particles will move freely. This means the movement or kinetic energy in particles gradually increases in the model.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.