Matter and Energy

The table  shows data from a laboratory experiment in which Andrew measured the temperatures of water in various states. Which of the following would be a correct conclusion from this experiment?

• The particles in iced water have less energy than the particles in ice have.
• The particles in ice have more energy than the particles in water have.
• The particles in iced water have more energy than the particles in boiling water have.
• The particles in boiling water have more energy than the particles in iced water have.

Which of the following sentences best describes the process that happens when liquid water becomes ice?

• Energy is added to the water, so its particles move more slowly.
• Energy is added to the water, so its particles move more quickly.
• Energy is removed from the water, so its particles lock into place.
• Energy is removed from the water, so its particles move more randomly.

Which of the following could describe oxygen at room temperature?

• It has a constant volume and a definite shape.
• It has a constant volume but takes the shape of its container.
• Its particles move fast enough to overcome the attraction between them.
• Its particles have a very orderly, three-dimensional arrangement.

Kevin compared the viscosities of several fluids. Substances A, B, and C flowed at different rates, but substance D did not flow at all. Which of the following is a valid conclusion?

• Substance D must be at its melting point.
• Substance D’s particles have strong attraction for one another.
• Substance D is neither a liquid nor a gas.
  
• Substance D’s particles have little attraction for one another.

In a laboratory experiment, Joel observed water as it vaporized, froze, melted, and condensed. Which of the following is a valid conclusion?

• He observed four different changes of state.
  
• He observed two different chemical changes.
• All of the changes required energy to be absorbed.
• All of the changes required energy to be released.

A cup filled to the rim with water was left at room temperature overnight. The figure above shows how much water was left the next morning. Which of the following is a reasonable hypothesis for what happened to the water?

• The water molecules at the surface lost enough energy to evaporate.
• The water molecules at the surface gained enough energy to evaporate.
• The water molecules at the surface lost enough energy to condense.
• The water molecules at the surface gained enough energy to sublimate.

A sealed, inflated beach ball was placed in a freezer overnight. The next day, the ball was still sealed but had shrunk. Analyze the following hypotheses to determine which is the best.

• The pressure inside the ball increased, so the gas particles moved faster.
• The gas inside the ball escaped, which caused the ball to shrink.
• The temperature of the gas increased, which pushed gas out of the ball.
• The temperature of the gas decreased, so the particles of gas moved closer together.

In a laboratory investigation on changes of state, Rebecca observes that the melting point of water is 0°C and that the freezing point of water is 5°C. What conclusion can Rebecca draw from these observations?

• Both melting and freezing are exothermic reactions.
• Water boils at 0oC at normal atmospheric pressure.
  
• Melting and freezing cannot occur at the same temperature.
• She made an error in her measurements.