Phase Changes Assignment and Quiz

The arrows in the chart below represent phase transitions. mc014-1.jpg Which arrows represent the phase transitions in which heat energy is gained?

1, 2, and 3

Which energy change occurs during boiling?

Heat energy is absorbed by the substance.

Energy is released during which phase changes? Check all that apply.

condensing depositing freezing

Which best describes the energy change that takes place during deposition?

Heat energy is released by the substance.

The diagram below shows the different phase transitions that occur in matter. mc027-1.jpg Which statement best describes the process that arrow 1 represents?

Molecules are speeding up as boiling occurs.

Which statements describe phase changes? Check all that apply.

Particles in a liquid need to move more slowly in order to freeze. Attractive forces between the particles in a liquid are broken when a liquid boils.

What does the diagram show about phases and the phase of the substance as it is heated? Check all that apply.

The particles are close together but move in different directions between 0°C and 2,200°C. The speed of the particles increases in region 5.

Use kinetic-molecular theory to describe what happens when an ice cube or icicle melts. Include how energy is involved and what happens to the motion of the water molecules

The particles in a solid move faster as the solid absorbs heat. The particles in a solid overcome the attractions that hold them together as the solid melts. The particles slide past one another, but are still close together during the liquid phase.

Which statement describes how phase changes can be diagrammed as a substance is heated? Which statement describes the appearance of a temperature-vs.-time graph?

The temperature is on the y-axis and the time is on the x-axis. Horizontal lines where the temperature is constant during phase changes connect upward-sloping lines where the temperature increases.

Consider the temperature versus time graph below. mc020-1.jpg At what temperature is the boiling point of this substance?

at 120°C

The diagram for gallium will have flat, horizontal lines __________°C. The diagram for methane will have a _______ line representing the _________ between -183°C and -162°C. For gold, the boiling point corresponds to the y-value at __________°C of the __________. For nitrogen, the line at -210°C will be ________, which represents the _______________.

at 30 and 2.204 diagonal, liquid phase 2,856, top horizontal line flat, the change from a solid to a liquid

The diagrams below represent the four states of matter. Which diagram represents the phase that occurs after a solid melts?

diagram 1

Jean has a sample of a liquid. If she changes the liquid's phase by __________ it, the molecules will spread out, allowing the sample to expand and fill a container of any shape or volume.

evaporating

Which example involves a phase change in which heat energy is released by the substance?

freezing ice cream

Water is initially present in a state where its molecules are far apart. During a change of state, its molecules slow down. Which change of state has most likely taken place?

from a gas to a liquid

When the temperature in a room increases from 25°C to 33°C, ______ changes from a solid to a liquid. In a lab, methane and nitrogen are cooled from -170°C to -200°C. The methane freezes and the nitrogen _______. When gold is heated to 2,856°C it changes from a liquid to a _____

gallium condenses gas

In which phase transition do molecules directly move from a state involving vibration of particles in a fixed position to a state involving random movement of high-speed particles?

sublimation