States of Matter
What are the three main states of matter?
Answer: Solid, liquid, gas.
A substance made of only one type of atom is called a what?
Element (a pure substance)
The ability to be bent into thin sheets
Malleable
How is density calculated?
Answer: Density is calculated using the formula Density=Mass/Volume
Give an example of a physical change.
Answer: Melting ice or boiling water.
In which state of matter are particles far apart and moving very fast?
Gas
How can you separate a mixture?
Answer: Techniques include filtration, distillation, and chromatography.
Elements that are dull, brittle, and poor conductors are called what?
Nonmetals
If an object floats in water, its density is (greater than / less than) water?
Less than water
The formation of a gas during a reaction is evidence of what?
Chemical Change
Which state of matter has a definite shape and a definite volume?
Solid
What is the difference between a homogeneous and heterogeneous mixture?
Answer: Homogeneous mixtures have uniform composition, while heterogeneous mixtures have visibly different components.
What is a metalloid?
Answer: A metalloid has properties of both metals and nonmetals; an example is silicon.
What is the density of water?
1 g/ml
The formation of a solid during a chemical reaction is called what?
Precipitate
Rank the states of matter from lowest to highest kinetic energy
Solid--Liquid--Gas
Give an example of a solution.
Answer: Saltwater or sugar dissolved in water.
The ability to allow the flow of heat and electricity
Conductor
If an oil layer is floating on water, what does that tell you about its density?
The oil is less dense than water.
During a science class experiment, a teacher places a small amount of paper pieces in a spoon and heats it over a candle. Which of the following is the best evidence that a change in the paper pieces chemical properties has occurred?
a. paper pieces get smaller
b. paper pieces become wet
c. paper pieces emit smoke
d. paper pieces curl on the edges
C. Paper pieces emit smoke
Which of the following do liquids and gases have in common? Select TWO correct answers.
A. They have a definite shape.
B. They take the shape of their container.
C.They are more compact than a solid.
D.Their molecules move faster than a solid.
E. Their molecules are less energetic than a solid.
B. They take the shape of their container.
D.Their molecules move faster than a solid.
Components in our environment can be classified as elements, compounds, or mixtures. Which object(s) can be classified as a mixture?
a. salt
b. sand
c. gold ring
d. water
e. aluminum can
f. soil
Sand and Soil
Rare Earth elements are important in modern technology. Name one device that uses them.
Smartphones, computers, electric cars, magnets, satellites, etc.
Explain water displacement.
the volume of an irregular shaped object. to find the volume, subtract the final water level from the starting water level.
How can you tell if a chemical change has occurred?
Answer: Indicators include color change, gas production, temperature change, or the formation of a precipitate.