States of Matter
A student pours water into a cup. The water takes the shape of the cup but keeps the same amount of space. What state of matter is the water?
Liquid
A student pours sand into a cup of water. After stirring, the sand can still be seen and settles to the bottom. What type of mixture is this?
Heterogeneous mixture
A student accidentally mixes iron filings with sand. Which tool would allow the student to remove the iron without picking up the sand?
Magnet
A student places an object in water. The object floats at the surface. What can you conclude about the object's density compared with water?
The object's density is less than water
A student observes that a piece of metal is shiny, silver-colored, and attracted to a magnet. These observations describe what?
Physical properties
A balloon is filled with helium. The particles inside the balloon are spread far apart and move freely. What state of matter is the helium?
Gas
A student completely dissolves sugar in a glass of water. The sugar is no longer visible, and the mixture looks the same throughout. What type of mixture is this?
Homogeneous mixture
A student has a mixture containing small rocks and sand. The student wants to separate the materials based on their different particle sizes. What method would work?
Sieving/screening
Four liquids have densities of 0.85 g/mL, 0.90 g/mL, 1.00 g/mL, and 1.03 g/mL. They are poured into the same container. Which liquid will form the bottom layer?
1.03 g/mL
A student needs to identify an unknown liquid without changing it into a new substance. Which types of characteristics should the student compare?
Physical properties
Ice cubes are placed in a glass. The particles are packed closely together and vibrate in fixed positions. What state of matter is the ice?
Solid
A bowl contains lettuce, tomatoes, cheese, and onions. You can see the different substances throughout the bowl. What type of mixture is this?
Heterogeneous mixture
A student mixes sand and water and allows the container to sit undisturbed. The sand collects at the bottom. What physical property allows the materials to be separated this way?
Differences in density
A mystery liquid has a density of 0.79 g/mL. Water has a density of 1.00 g/mL. If the liquids are poured together, where will the mystery liquid be?
Above the water
A student tests three substances. Substance A is attracted to a magnet, while Substances B and C are not. What physical property is the student testing?
Magnetism
A student heats a substance and observes that its particles begin moving faster and spreading farther apart. What happens to the particles' kinetic energy?
It increases
Two students are given a clear liquid. One student says it must be a pure substance because it looks the same throughout. Why could this conclusion be incorrect?
A homogeneous mixture can look the same throughout
A student has a mixture of iron filings and sand. After using a magnet, some sand remains behind. Why was the magnet able to separate the two materials?
Iron is magnetic and sand is not
A student pours several liquids into a container. Liquid A has a density of 0.79 g/mL, Liquid B has a density of 1.05 g/mL, and Liquid C has a density of 1.60 g/mL. Which liquid will be closest to the bottom?
Liquid C
A scientist measures the mass and volume of an unknown liquid and uses those measurements to determine how tightly its matter is packed. What property is the scientist determining?
Density
Three samples contain the same number of particles and have the same mass.
Sample A has particles packed tightly together.
Sample B has particles that can move past one another.
Sample C has particles spread far apart.
Which sample has particles with the greatest kinetic energy?
Sample C
A student compares salt, salt water, and a salad. The salt contains one type of particle, the salt water contains salt evenly distributed throughout water, and the salad contains visibly different parts. Which one is the pure substance?
Salt
A student wants to separate a mixture but does not want to create a new substance. Should the student use a physical or chemical change?
Physical change
A scientist has five liquids with densities of 0.79, 0.90, 1.00, 1.05, and 1.60 g/mL. The scientist wants to pour them into a container from least dense to most dense. Which liquid should be poured first?
0.79 g/mL
A student has three unknown substances. One is a clear liquid, one is a white powder, and one is a shiny substance that is attracted to a magnet. Based only on the observations, what can the student conclude about the shiny substance?
It has magnetic properties and is likely a metal