Grade 8 Study Guide – Science- Exam date: Wednesday, June 6 th
Scientist
John Dalton
-
He believed that matter was made of atoms that were too small to be
seen by the human eyes
His model became known as the atomic theory of matter
Lavoisier
-
He is the founder of modern chemistry
He presented the law of conservation of matter
JJ Thomson
-
He discovered the electron – he won the noble prize of physics for this
discovery
He realized that the atom contained positive and negatives charges
Rutherford
-
He found that atoms must be made of mostly empty space
He found the nucleus
He named the positively charged particles in the nucleus protons
Chadwick
-
He discovered the neutron
Bohr
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Made the first model of the atom
Vocabulary Terms
1. BOILING POINT: The temperature at which a liquid turns to a gas
2. MELTING POINT The temperature at which a solid turns to a liquid
3. FREEZING POINT: The temperature at which a liquid turns to a solid (32)
4. FLAMMABILITY: The ability to burn
5. REACTIVITY: The ability of a matter form to react chemically with another
form of matter
6. DUCTILE: The ability for a substance to draw into wires so contact can be
made
7. PHYSICAL PROPERTITY: Characteristics of matter that can be seen through
direct observation such as density, melting point, boiling point, and
freezing point
8. PHYSICAL CHANGE: Change in which the identity of the substance does
NOT change
9. CHEMICAL PROPERTY: Characteristic of matter that can only be observed
when one substance changes into a different substance such as iron into
rust
10. CHEMICAL CHANGE: Transforms one type of matter into another kind,
which may have different properties
11. PRESSURE: The force applied to an object
12. VISCOCITY: the resistance of a liquid to flow
13. FORCE: exerted pressure- push or pull
14. FLUIID: a substance whose shape can easily change
15. MATTER: Anything that has mass and takes up space
16. ELEMENT: Matter made up of only one kind of atom
17. COMPOUND: A pure substance whose smallest unit is made up of atoms or
more than one element
18. ATOM: A small particle that makes up most types of matter on Earth
19. NUCLEUS: Positively charged central part of the atom
20. PROTON: Positively charge particle in the nucleus of the atom
21. NEUTRON: Uncharged particle in the nucleus of the atom
22. ELECTRON: Negatively charged subatomic particle
23. LAW OF CONSERVATION OF MATTER: States that matter is not created or
destroyed but only changes its form
24. Atomic #- states the # of protons
25. Chemical symbol: stands for the element name
*Rule- the 1st letter is capital, 2nd letter is lower case
26. Atomic mass unit (a.m.u.)- states
the number
the mass of the particles * always round
27. Period #- found on the left side of the chart- it states the number of energy
levels
28. VALENCE: is the energy level farthest from the nucleus
29. To find the # of neutrons: Subtract the atomic number from the estimated
a.m.u.
30. QUARKS: Broken down protons and neutrons into smaller parts
31. COMPOUNDS: substances that are made up of more than one type of
atom
32. MIXTURE: made up of two or more substances that are physically
combined
33. SUBSCRIPT: states the # of atoms per elements
34. MONOATOMIC: one molecule made up of one atom
35. DIATOMIC: one molecule made up of two atoms
………………………………………………………………………………………
Here are some key words to be familiar with:
Physical changes:
Chemical changes:
Evaporating
burning
Melting
digesting
Heating
corrode
Cracking
ferment
Meting
rust
Mixing
oxidize
Boiling
tarnish
Condense
explode
The 5 states of matter:
1.
2.
3.
4.
5.
Liquids
Solids
Gases
Plasmas
Bose Einstein condensates
……………………………………………………………………………………………..
Know how to do the incomplete diagram for elements- part 1
For example, using the element Se
Symbol-
Se
Atomic #-
34
Est. amu-
74 amu
#P-
34P
#N-
45N
#e-
34e
Group #-
16A
Period #-
4
Mass#-
34P+45N= 79 amu
Know the key terms & parts of the elements found on the PTOE
1A
11
3
Na
Sodium
22.99707
(23)