Grade 9 Chemistry Mid-Term

Front 1

observation/inference

Back 1

observation: quantitative and qualitative

qualitative:using your senses, qualitative: numerical, involves measurment

inference: are conclusions that you make based on observations

Front 2

variables Independent

Back 2

Independent variable is the variable that you adjust or change,

Front 3

examples of variable independent/dependent and control

Back 3

lights(independent variables)

growth rate(dependent variable)

pots,location,soil,species of plant,brand of light,conditions,temperature(constant variable)

Front 4

PARTICLE THEORY

Back 4

particle theory states that all matter consists of many small particles which are constantly moving or are in a continual state of motion.

Front 5

FIVE POINTS OF THEORY

Back 5

1. all matter is made up of tiny,invisible particles

2. particles have empty spaces between them

3. particles move faster and further apart when they are heated

4. particles attract each other, so they tend to stick together rather than fly apart

Front 6

states of matter

Back 6

solid , liquid , gas

Front 7

physical and chemical properties

Back 7

physical property: is observed with senses and is determined without destroying matter

chemical property: indicates how a substance reacts with something else and that the matter will be changed into a new substance after the reaction

Front 8

physical properties

Back 8

melting point, boiling point, viscosity, ductility,malleability, density, solubility

Front 9

chemical properties

Back 9

combustibility, reaction with acid, flammability, light sensitivity

Front 10

physical/chemical change

Back 10

physical change occurs when thee substance changes is size,shape or form and no new substance is formed

chemical change occurs when there is a change in the physical and chemical properties, and a new substance is formed (5 indicators are odour,colour,temp.,gas bubbles and precipitate)

Front 11

matter

Back 11

anything that has volume and mass

Front 12

classification of matter

Back 12

Matter can be classified into two basic categories. Matter is either a mixture or it is a pure substance. We can classify mixtures into two categories - Homogeneous mixtures and heterogeneous mixtures. We can also classify pure substances into two categories - Elements and compounds.

Front 13

element(s)

Back 13

element = a pure type of matter composed of all the same atoms
Example: again, hydrogen, helium, anything found on the periodic table.

Front 14

atoms and molecules

Back 14

atoms: is the basic unit of a chemical element

molecule: combination of atoms (same element or different) joined chemically.

Front 15

compound

Back 15

compound = pure substance made of 2 or more elements by a chemical reaction (different elements)

Example: HCl or H2O

all compounds are molecules but not all molecules are compounds. compounds are made up of elements

Front 16

mixture

Back 16

mixture = combining substances in such a way that no chemical reaction occurs (different parts can still be picked out).
Example: tossed salad, chicken noodle soup, salt water

Front 17

law of definite proportions

Back 17

The Law of definite proportions states that no matter how you make a chemical compound, it's got the same ratio of elements. An example: Whether you make water by combining hydrogen and oxygen or by decomposing hydrogen peroxide, the resulting water will still be 1 part by mass of hydrogen to eight parts by mass of oxygen.

Front 18

proton

Back 18

is relatively large has a positive charge and is found in the nucleus

Front 19

neutron

Back 19

has a no charge,so it is neutral charge , found in the nucleus and is relatively large

Front 20

electron

Back 20

has a negative charge, is very small and is found outside of the nucleus

Front 21

atomic mass and number

Back 21

Atomic mass is the sum of the masses of the protons, neutrons, and electrons in an atom, or the average mass, in a group of atoms.

Atomic number is the number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table

Front 22

Bohr Rutherford diagram

Back 22

Front 23

lewis dot diagram

Back 23

Front 24

general atomic theory

Back 24

dalton proposed all matter consisted of tiny particles called atoms

Thomson's model of the atom is 'plum pudding'

Rutherford's model of the atom is called planetary model

Bohr-Rutherford model is the refined version of the original Putherford model.

Schrodinger showed that electrons move in a region on space which is often represented visually as a cloud.

Front 25

STRUCTURE OF THE PERIODIC TABLE

Back 25

1. each element has a box

2. ordered by the atomic number

3. the columns are called groups, same valence electrons(outer shell)

4. the rows are called periods, same energy levels(shell number)

5. special groups 1,2,17,18 Alkali metals, Alkaline metals, Halogens, Nobel Gas

6. metal/non metals/ metalloid location is the 'staircase'

7. reactivity/ trends

Front 26

dependent variable

Back 26

Dependent variable is the responding variable,the outcome

Front 27

constant

Back 27

Constant: factors in the experiment which do not change throughout the entire experiment

Front 28

control

Back 28

Control variable that gets tested without change, does NOT have the experimental variable