Atoms
What is an atom?
The smallest unit of matter
If you combine two hydrogen atoms (H) and one oxygen atom (O), what molecule would form?(EQ#10 and EQ#2)
H₂O (water) (EQ#10 and EQ#2)
How are the particles in a gas different from those in a solid? (EQ#6)
They are farther apart and more active. (EQ#6)
H₂O
Water
How does heat energy affect the density of matter? (EQ#12)
Adding energy or heat reduces density. (EQ#12)
How are atoms like Legos?
They can be put together many different ways.
How is carbon dioxide (CO₂) different from atmospheric oxygen (O₂)?
It has a carbon atom.
What happens to the particles of a solid when heat energy is added? (EQ#4)
They gain energy, move apart and the solid becomes a liquid. (EQ#4)
NaCl
Salt
When a gas condenses into a liquid, does it lose or gain heat energy? (EQ#14)
It loses energy. (EQ#14)
What is at the center of an atom?
Nucleus
Can a molecule be made from just one type of atom? Give an example.(EQ#8 and EQ#11)
Yes, atmospheric oxygen is O₂. (EQ#8 and EQ#11)
What is the difference between melting and freezing? (EQ#5)
Melting is adding energy to a solid to form a liquid. Freezing is removing energy from a liquid to form a solid. (EQ#5)
O₂
Atmospheric oxygen
Why do ice cubes melt faster on a hot day than on a cold day? (EQ#15)
The air has more heat energy, so more energy is transferred. (EQ#15)
What are the three particles in an atom?
Proton, neutron, electron
What would happen to the molecule if the number of atoms changed (e.g., CO₂ vs. CO)? (EQ#9)
The properties of the substance would be different.(EQ#9)
What phase change happens when water turns into steam? (EQ#7)
Evaporation (EQ#7)
H₂O₂
Hydrogen Peroxide
Dry ice changes from a solid to a gas. What is this process called?
Sublimation
What is the difference between an atom and a molecule? EQ#1
An atom is one. A molecule is two or more atoms bonded together. EQ#1
Sodium (Na) is explosive. Chloride (Cl) is a poisonous gas. How can we put them on our food?
NaCl or salt is different from the atoms that form it.
What happens to the particles in a liquid when it freezes? (EQ#13)
The particles slow down and move close together. (EQ#13)
CO₂
Carbon dioxide
We study three states of matter, but there is a fourth. What is it?
Plasma