States of Matter
Name the three common states of matter.
Solid, liquid, and gas.
In which state of matter are particles tightly packed and vibrating in place?
Solid.
What happens to an ice cube when it gains enough heat energy?
It melts into liquid water.
Is ice cream melting a physical or chemical change?
Physical Change.
True or False: Melting butter creates a new substance.
False. It is a physical change.
Which of these is NOT a state of matter: solid, liquid, gas, or density?
Density
Are particles in a gas closer together or farther apart than particles in a liquid?
Farther apart.
What happens to liquid water when it loses enough heat energy and reaches its freezing point?
It freezes into solid ice.
What type of change happens when an object changes shape but does not become a new substance?
Physical Change.
What is a physical combination of two or more substances without creating a new substance?
Mixture.
Ice, liquid water, and water vapor are three different _____ of the same substance.
States of matter
In which state of matter can particles move past one another while remaining close together?
Liquid.
What state can liquid water become when enough heat energy is added?
Gas (water vapor).
Baking soda and vinegar react and produce carbon dioxide gas. What kind of change occurred?
Chemical change.
Name TWO possible signs that a chemical reaction has occurred.
Examples: gas formation, temperature change, color change, or formation of a solid precipitate.
Which state of matter has a definite shape and a definite volume?
Solid
Why can gas spread out to fill an entire container?
Gas particles move freely and are spread far apart.
What is the name of the process when a gas changes into a liquid?
Condensation.
A sliced apple turns brown after sitting out. What type of change occurred, and why?
Chemical change. The apple reacts with oxygen, forming new substances that cause browning.
A student mixes salt and pepper in a bowl. Is this a physical or chemical change? Explain.
Physical change. The substances are mixed but no new substance forms.
A student pours water from a cup into a bowl. Why does the water change shape but not volume?
A liquid takes the shape of its container but keeps a definite volume.
Why can you see ice and liquid water, but not ordinary water vapor?
Ice and liquid water are visible in bulk, but water vapor is an invisible gas dispersed in the air.
A cold glass of water develops droplets on the outside. Where did those droplets come from?
Water vapor in the surrounding air cooled and condensed into liquid water.
A student breaks a glass cup into several pieces. Explain why this is a physical change.
The glass changes size and shape, but it is still glass; no new substance forms.
A student observes bubbles when two liquids are mixed. Does this prove a chemical change happened? Explain.
Not necessarily. Gas production can be evidence of a chemical reaction, but bubbles alone are not proof; more evidence is needed.