Chemistry Test Prep Flashcards
Plum Pudding
D: An atom is a positive sphere embedded with negative electrons
Scientist: JJ Thomson
Billiard Ball
An atom is solid sphere similar to a billiard ball
Scientist: John Dalton
An atom consists of a tiny positively charged nucleus, surrounded mostly by empty space containing negative electrons
Scientist: Ernest Rutherford
Gold foil experiment
Ernest Rutherford
Electric current in gas discharge tubes
JJ Thomson
Make hydrogen gas glow by passing an electric current through it
Niels Bohr
Planetary Model
Niels Bohr
Ice disappears in a drink
Melting, Absorbed (endothermic)
Frost forms on your lawn
Deposition, Released (Exothermic)
Snow melts without a trace
Sublimation, Absorbed (ENDO)
Raining
Condensation, released (Exothermic)
Snowing
Deposition, released (exothermic)
Car windows fog up
Condensation, released (Exothermic)
What happens to the temp during a change of state?
It remains constant
Describe what happens to the particles as heat is added?
Particles move faster and farther apart
What are the 4 points of kinetic molecular theory (kmt)?
-All matter is made up of very small particles
-There is empty space between the particles
-The particles are constantly moving
-Energy makes the particles move
Fill in the blanks:
Solid:
Shape:
Volume:
Space between particles:
Movement of particles:
Volume: Fixed
Shape: Fixed
Space between particles: Tightly packed together
Movement of particles: Vibrate
Fill in the blanks:
Liquid:
Shape:
Volume:
Space between particles:
Movement of particles:
Shape: Not fixed
Volume: Fixed
Space between particles: Farther apart and a little bit more room than solid
Movement of particles: Slip and slide past each other
Fill in the blanks:
Gas:
Shape:
Volume:
Space between particles:
Movement of particles:
Shape: Not fixed
Volume: Not fixed
Space between particles: Very far apart, there are large spaces between particles
Movement of particles: Move quickly and freely
Salt dissolves in water
Chemical
Cooking a hotdog
Chemical, Absorbed (Endo)
Precipitate forms
Chemical
Dew evaporates off of grass
Physical, Absorbed (ENDO)
Candle burning (anytime anything burns its chemical change)
Chemical, Released (EXO)
Condensation forms on a mirror
Chemical, Released (EXO)
Pure substance
Made up of only one type of matter
Element
Pure substance which cannot be broken down any further and is made up of only one type of atom
Compound
Pure substance which is made up of two or more different types of elements
Precipitate
Solid forms in a liquid
Exothermic
A chemical or physical change which releases energy/heat
Endothermic
A chemical or physical change which absorbs energy/heat
What subatomic particle has a positive charge
Protons
What subatomic particle determines the size of the atom
electrons
Two particles that are almost equal in mass
Protons and Neutrons
Has a negative charge
Electrons
Found in the nucleus
Protons and Neutrons
Contributes to the mass of the atom
Protons and Neutrons
Has negligible mass
Electrons
ALWAYS equal to the atomic number
Protons
Two particles that exist in equal numbers in a neutral atom
Protons & Electrons
