States of Matter
What are the three states of matter
Solid, Liquid, Gas
What is the average kinetic energy of a substance the same as?
Temperature
What is kinetic energy?
The energy of movement
Juan and his science class are constructing models of sugar crystals. He wants his model to show how the sugar molecules move in the crystal. He is using plastic foam balls to represent the sugar molecules. How should he put the plastic foam balls together to make his model?
A. Connect them with stiff springs
B. Fill a clear cube with them
C. Glue them together
A. Connect them with stiff springs
- the springs will allow the particles to vibrate in place
Please come up to the board and draw a picture with the molecules of a substance in the three states
solid: ..............
liquid: . . . . . .
gas: . . . . .
Define freezing point
When a liquid changes to a solid
What happens to the molecules of a substance when there is an input of energy?
They speed up
Your teacher gives you a container with a clear liquid in it. The liquid is a pure substance. What could you do to help you identify the liquid in the container?
A. Measure the volume of the liquid and compare it to the volumes of other liquids
B. Measure the temperature of the liquid and compare it to the temperature of other liquids
C. Determine the boiling point of the liquid and compare it to the boiling points of other liquids
C. Determine the boiling point of the liquid and compare it to the boiling points of other liquids
True or False:
All atoms and molecules have their own internal kinetic energy
TRUE
Define Melting Point
When a substance changes from a solid to a liquid
Nora notices water droplets on the grass in the morning. It did not rain during the night. How can the water particles in the air form water droplets on the grass during the night?
A. Energy was added to the water particles, causing attraction that makes them move closer together
B. Energy was taken away from the water particles, allowing them to move farther apart
C. Energy was taken away from the water particles, allowing them to move closer together
C. Energy was taken away from the water particles, allowing them to move closer together
- as energy is removed from the gas particles, they move closer together until the attraction between the particles is great enough for them to be held as a liquid
During several trials, a group of scientists tests the reaction of a new medicine on a strain of bacteria. Which step is essential for proving the validity of the results?
A. Make the process public so the results can be replicated
B. Change the procedure to check whether the same results take place
C. Have another scientist check to make sure the medicine was properly produced
A. Make the process public so the results can be replicated
True or False:
The mass of substances changes as the substance changes states of matter
FALSE
The law of conservation of mass
Define Boiling Point
When a substance changes from a liquid to a gas
How does the temperature of water vapor change when it is made into clouds?
A. It decreases
B. It increases
C. It does not change
C. It does not change
- The energy is released by the water molecules as they form intermolecular bonds
-Temperature does not change as the state of matter changes
Compounds that have the same chemical composition may have different densities. Which of these statements explains this fact?
A. The compounds vary in their solubility in water
B. The compounds vary in their ability to bond with hydrogen
C. The compounds exist in different states (solid, liquid, gas)
C. The compounds exist in different states (solid, liquid, gas)
What must be broken in order for a substance to change states?
Intermolecular Bonds
Define Evaporation
When a liquid changes to a gas before the boiling point is reached
Freezing temperatures can destroy citrus crops. Citrus growers sometimes spray water on the fruit to protect it from freezing. How can spraying the trees with water protect the fruit?
A. The temperature of the water will change as it freezes
B. The water releases energy to its surroundings as it freezes
C. The water takes in energy from its surroundings as it freezes
B. The water releases energy to its surroundings as it freezes
Raul and Bonnie are trying to classify several objects that they found during a field trip to the beach. They collected a sample of seawater, a piece of driftwood, and several smooth pebbles. What property does the driftwood share with the pebbles that it does not share with the water?
A. Its particles move freely in all directions
B. Its particles vibrate, but are locked in place
C. Its volume does not depend on its container
B. Its particles vibrate, but are locked in place