Unit 1
Explain climate vs weather
Weather: Short term
Climate: Long term patterns
What is ionization?
When an atom gains or loses an electron, giving it a charge
How many atoms/particles are in one mole?
6 x 10^23
Identify each substance as an acid or a base:
HCl and NaOH
HCl: Acid
NaOH: Base
Explain how kinetic energy and potential energy in a reaction are related
As one increases, the other decreases
List a material with a low specific heat
Metal
Explain how charge and force impact electrostatic force
Charge= more charge, more force
Distance= less distance, more force
What is the difference between adhesion and cohesion?
Adhesion: Water molecules stick to other substances
Cohesion: Water molecules stick to other water molecules
Which is stronger: A substance with a pH of 2 or a substance with a pH of 5? Are these substances acids or bases?
pH of 2 is stronger (more H+ ions), acid
What gets created whenever fuel is burned (gasoline, diesel, propane, etc)? Why?
How does heat move between objects of different temperatures
From hot to cold until they are the same temperature
Draw an electron dot diagram for oxygen
Answer
How many bonds does oxygen want to form? Why?
2 bonds, it needs 2 more valence electrons to have a complete shell of 8 valence electrons
What is the law of conservation of energy?
Energy cannot be created or destroyed, but it can be transformed
Explain what happens to energy when a bond is broken
Energy is absorbed to break the bond
The particles motion would increase and there would be more collisions.
What causes a molecule to be polar
Atoms have different electronegativities, which mean some atoms pull electrons closer to their nucleus then others
Draw/explain why water polar molecules
Answer
Explain how temperature and concentration impact reaction speed
higher temp=faster
more concentrated= faster
Why does diesel release more energy than gasoline when burned?
Diesel is bigger, more atoms to form new bonds with
Explain conduction, radiation, and convection
Conduction: Transfer of heat through touching
Convection: Transfer of heat through motion of particles in a liquid or gas
Radiation: Transfer of heat from electromagnetic waves
Why is pure water NOT a conductor of electricity?
Pure water has no ions dissolved in it, so there is nothing to carry the charge
Calculate the electronegativity difference between hydrogen and oxygen. Then say what type of bond it forms
1.24, polar covalent
Draw/explain neutralization
Acids and bases reacts and combine to form water (neutral)
H+ + OH- --> H2O
energy released
temp increases
bonds form