chemistry - grade 9

1. all matter is made up of particles

2. all particles have a little space between them

3. all particles in a substance are identical

4. all particles are in constant motion

5. all particles in the same substance are attracted to each other

1. energy

2. speed

3. distance

4. attraction

the study of matter and the changes it undergoes

1 type of particle combined by chemical means

2 of the same atom

H, O, F, Br, I, N, Cl

1 atom

2 or more different atoms that are chemically combined

a compound/substance with only 1 type of atom

2 or more particles combined by physical means

1 visible phase

when a solute is dissolved in a solvent

metals melted together

2 visible phases

all parts are visible and can be separated

particles suspended in a gas or liquid

characteristic of a substance that happens during a reaction

described or measurable characteristic of matter

luster, clarity, brittleness, ductility, viscosity, hardness, malleability

density, boiling point, freezing point, melting point

D=M/V

V=M/D

M=V x D

a name for a type of atom

protons (+) electrons (-) neutrons (neutral)

ductile, malleble, lusterous, conductive

not conductive

found on the staircase and have properties of both metals and non-metals

number of protons

mass of protons + neutrons

atomic mass: 9 amu

atomic number: 4

atomic mass: 23 amu

atomic number: 11

• type of element

• same number of proton

• different number of neutrons/mass

looking at the ratio of C-12 to C-14 in a substance to see how many thousands of years an organism has been dead

Nitrogen. It also takes 5,730 for half of it to turn back into Nitrogen

the number of orbitals

the number of valence electrons

• alkali metals

• lustrous, silvery, soft, highly reactive

• alkaline earth metals

• burn bright colorful flames

• lustrous, silvery

• not as soft of reactive as group 1

• transition metals

• different states of matter

• conductive

• high melting and boiling points

• halogens

• highly reactive

• different states of matter

• poisonous in large amounts

• noble gases

• colorless, odorless, tasteless

• stable

• glow brightly when electricity passes through

it shares similar properties like 1 valence electron and reactivity

came up with the idea of small indivible particles called atoms

rejected the idea of atoms, thought everything is elemental

billiard ball model, all atoms of a specific are the same

chocolate chip cookie model, electrons being evenly disturbed inside positive space

discovered protons + nucleus, predicted the discovery of neutrons. Together these subatomic particles make up the mass of atoms. Also stated that electrons surrounded the nucleus in a cloud

said electrons orbit nucleus in shells like planets (bohr-rutherford planetary model)

discovered neutral subatomic particles called neutrons. Said that neutrons and protons make up the mass of atoms

a universally accepted fact, the foundation of science

an educated guess, can be disproven or proven with just one experiment

explanation for a set of observations, based upon verified hypothesis. NOT a fact

change in state/arraignment, no new substance formed (ex: freezing)

2 substances react to form new subsance

• new color

• new odor

• precipitate (solid made from 2 liquids)

• hard to reverse

• gas formation

charged atom

looses electrons to become a positively charged atom. Looses electrons if it has less than 4 electrons

gains electrons to become a negatively charged atom. gains electrons if it has more than 4 electrons

5 molecules

10 Al

15 S

60 0

2 Na

1 S

4 O