Atom Structure and Properties
What are protons, neutrons, and electrons?
The 3 subatomic particles in an atom — protons (+), neutrons (0), electrons (–).
What type of bond happens between a metal and a nonmetal?
Ionic bond.
What force holds water molecules together?
Hydrogen bonding.
What’s the Law of Conservation of Mass?
Mass can’t be created or destroyed in a chemical reaction.
What does the rate of a reaction mean?
How fast the reaction happens.
Where are electrons found in an atom?
In energy levels (or shells) outside the nucleus.
What’s a covalent bond?
When two nonmetals share electrons.
Which force is weakest: dispersion, dipole-dipole, or hydrogen bonding?
Dispersion forces.
Balance this: H₂ + O₂ → H₂O
2H₂ + O₂ → 2H₂O
How can you make a reaction go faster?
Add heat, stir, increase concentration, or use a catalyst.
What does the atomic number tell you?
The number of protons (and electrons if it's neutral).
Which one conducts electricity: ionic or covalent compounds?
Ionic compounds (when dissolved in water).
What happens to boiling point when IMFs are strong?
It goes up.
What’s a precipitation reaction?
Two solutions mix and form a solid.
What does a catalyst do?
Speeds up the reaction without being used up.
How do you find the number of neutrons?
Subtract the atomic number from the mass number.
What's the shape of water (H₂O)?
Bent.
What’s the deal with “like dissolves like”?
Polar dissolves polar, nonpolar dissolves nonpolar.
What’s an acid-base reaction?
An acid gives an H⁺ and a base takes it.
What’s activation energy?
The energy needed to start a reaction.
Why do ions exist?
Atoms gain or lose electrons to get a full outer shell (usually 8).
What's a polar molecule?
A molecule with uneven charge — like water.
Why is ice less dense than water?
Hydrogen bonds hold molecules farther apart in solid form.
What’s a redox reaction?
One thing loses electrons (oxidized), the other gains (reduced).
What’s the rate law?
An equation that shows how concentration affects rate.