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Chemistry Unit:
 The particle theory of matter
 States of matter
 Classification of matter
 Heterogeneous and homogeneous
 Chemical and physical properties
 Physical and chemical changes
 Dalton’s atomic theory
 Elements
 Atoms, molecules, and diatomic molecules
 Mendeleev’s periodic table – groups/columns and periods/rows
 Metals, non-metals, metalloids and noble gases
 Atomic number, symbols and atomic mass
 Subatomic particles – protons, neutrons and electrons
 Bohr – Rutherford diagrams
 Lewis Dot Diagrams
 Isotopes
Space Exploration Unit:
 Celestial bodies (types and motion)
 Ancient Civilizations
 Geocentric and heliocentric models
 The sun
 Inner and outer planets
 Order of the planets in the solar system
 Scale and planet models
 Astronomical units
 Asteroids, comets and meteors
 Evolution of the stars
 Big Bang Theory
Exam Practice Questions:
Chemistry:
1. Describe the four points of the particle theory of matter.
 All matter is made up of tiny particles.
 One substance is made up of all the same particles and different
substances are made of different particles.


Particles are always moving; the more energy the particles have, the
faster they move.
There are attractive forces between two particles. These forces are
stronger when the particles are closer together.
2. Draw an ice cube in its solid, liquid and gaseous states, using the particle
theory.
3. Describe the difference between a chemical and a physical property. Give an
example of each.
 A physical property is a characteristic or description of a substance that
may help to identify it. (colour, texture, odor, lustre, clarity, or taste)
 A chemical property describes the behaviour of a substance as it becomes
a new substance.
4. Describe what happens during a chemical change and a physical change.
• Physical Change: No new Substance is formed, the process can be
reversed. Example: Example: Ice melting into liquid water.
• Chemical Change: At least one new substance is produced. Cannot, or is
very difficult to, reverse. Example: Burning paper.
5. How can you tell the difference between a chemical and a physical change?
 A physical change is a change of state, change can be reversed
 A chemical change has occurred when :
o A new colour appears, Heat or light is given off, Bubbles of gas are
formed, A solid material (or precipitate) forms in a liquid, The
change is difficult to reverse
6. Describe if a physical or chemical change is taking place in the following:
a) Mixing salt and pepper; why?
Physical: No new substance has been produced, can separate
particles
b) Baking a cake; why?
Chemical: New substance, cannot reverse the process
c) Rust forming on metal; why?
Chemical: New substance, cannot reverse the process
d) Chocolate melting; why?
Physical: No new substance has been formed, reversible
7. Describe the difference between a compound and a molecule.
• Compounds are pure substances that are made up of two or more
different elements
• Molecule: Composed of 2 or more elements that are joined by chemical
bonds.
8. What is an atom?
 Atom: All matter is made up of atoms. Atoms are the smallest unit of an
element that maintains the properties of that element
9. Describe the 4 points of Dalton’s atomic theory.
1. All matter is made up of small particles called atoms.
2. Atoms cannot be created, destroyed, or divided into smaller particles.
3. All atoms of the same element are identical in mass and size, but are
different in mass and size from other elements.
4. 4. Compounds are created when atoms of different elements link
together in definite proportions.
10. Who created the periodic table?
 Dmitri Mendeleev
11. Explain how elements on the periodic table are arranged and describe the
importance of developing symbols for each of the elements.
• He organized each of the elements according to their atomic masses. As
new elements were discovered they fit into Mendeleev’s basic framework
for the periodic table.
• Previous to the periodic table there was no organization. Creating
symbols allowed universal recognition of the elements, regardless of
language barriers.
12. Explain the difference between groups and periods on the periodic table.
 Groups: Elements have similar physical and chemical properties. They are
the vertical columns.
 Periods: Horizontal rows have similar properties and gradual changes in
these properties.
13. What are some characteristics of Alkali Metals? Alkaline Earth Metals?
Halogens? Nobel Gases?
 Alkali: These elements are all shiny, silvery metals that are extremely
reactive.
 Alkaline Earth Metals: Shiny, silvery-white colour, highly reactive but not as
reactive as the Alkali metals
 Halogens: The halogens are the most reactive non-metals
 Nobel Gases: These gases are un-reactive and almost never form
compounds with other elements.
14. Describe the difference between metals, non-metals and metalloids.
 Metals: Metals are shiny solids are room temperature, with characteristic
high melting points and densities. Electrons in the valence shell of metal
atoms can be removed easily. Metals have the ability to be deformed
without breaking. They are found on the left side of the table. Good
conductors (able to transfer electricity and heat), Malleable (Can be
moulded into different shapes)
 Non-metals: They are generally poor conductors of heat and electricity.
Solid nonmetals are generally brittle, with little or no metallic luster. Most
nonmetals have the ability to gain electrons easily. They are found on the
right side of the table (except hydrogen). Often have a dull surface lustre
if they are a solid. Not malleable or ductile – usually brittle
 Metalloids: Elements that have both metallic and nonmetallic properties
are called metalloids
15. Draw and label the structure of an atom. Describe the subatomic particles.
16. Calculate the following:
Element
Mg
K
Be
F
Atomic #
12
19
4
9
Atomic Mass
24
39
9
19
# Protons # Electrons # Neutrons
12
12
12
19
19
20
4
4
5
9
9
10
17. Write the symbol for nitrogen using the proper notation.
 147N
18. Use the periodic table to complete the following:
Name of
Substance
Chemical
Formula
Compound or
Element?
Elements
present
How many
atoms of each
element?
helium gas
He
Element
Helium
1
Iron,
Sulphur,
Oxygen,
Hydrogen
Sulphur
Oxygen
Magnesium
Phosphorous
Oxygen
1
1
9
10
1
3
15
10
40
iron (II) sulfate
FeS04 - 5H2O
C
sulfur trioxide
SO3
C
Magnesium
phosphate
5Mg3(PO4)2
C
19. What is an ion?
 Atoms that have lost or gained electrons
20. Describe the difference between a cation and an anion.
 Cation: atoms that have lost an electron and have a positive charge
 Anion: atoms that have gained an electron and have a negative charge
21. Describe Neils Bohr’s contribution to science.
 Neils Bohr (1885 – 1962), explained why in the atom electrons do not
spiral into the nucleus. Bohr’s model equated the nucleus of an atom to
the sun, and the electrons to the planets.
 The atoms positive nucleus exerts a strong force of attraction on the
negative electrons.
22. Explain in full all parts of the Bohr diagram. Describe each structure and
state how the Bohr diagram relates to the periodic table.
 A Bohr diagram includes the protons and the neutrons located inside of
the nucleus. The electrons travel in energy shells around the outside of
the nucleus.
 Protons have a positive charge, neutrons are neutral, electrons have a
negative charge.
 The number of protons is the same as the atomic number of the element
and the protons plus the neutrons equal the atomic mass.
 The number of energy shells corresponds to the period of the element.
 The first energy shell can hold 2 electrons, the second can hold 8 and the
third can hold 8.
 The valence electrons for each Bohr diagram correspond to the group of
the element, and determines how an element reacts with other elements.
23. What is the outer shell called? What are the electrons in the outer shell called?
 Valence shells, valence electrons
24. Draw a Bohr diagram and a Lewis dot diagram for: Li, Mg and S.
25. What is an isotope?
• Atoms of the same element can have different number of neutrons; these are
called isotopes.
Symbol Isotope Name
Atomic Mass
# Protons # Neutrons
F
N-15
C-14
K
19
15
14
39
9
7
6
19
Fluorine
Nitrogen - 15
Carbon - 14
Potassium
10
8
8
20
Most Common?
Y/N
Y
N
N
Y
Space:
1. What is a Celestial body?
 Celestial bodies is the term used to describe the Sun, Moon and stars
2. Explain the importance of the sky to people from ancient civilizations. What
did they use the sky for?
– People watched the sky to tell: the time of day, the date, the
weather, their position on Earth, when the tides would be higher or
lower than usual.
3. Describe the main idea of the Geocentric model.
• Early scientists believed that the Earth was at the center of a giant sphere
on which the sun, moon and planets were attached.
4. Describe the main idea of the Heliocentric model.
• This model placed the Sun at the center with the Earth and other planets
travelling westward around it.
5. Explain how the two models are different and what led to the change in
perspective.

6. Describe the composition of the sun.
• The sun is a huge globe composed of mostly hydrogen and helium.
7. What occurs during a solar eclipse?
 The moon is in between the Earth and the sun blocking out the light from
the sun.
8. How are the planets in our solar system arranged?
 Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
9. List the inner planets and the outer planets.
 Inner: Mercury, Venus, Earth, Mars,
 Outer: Jupiter, Saturn, Uranus, and Neptune.
10. Describe the differences between the inner and outer planets.
 Inner planets are closer to the sun and are terrestrial (made of rock), the
outer planets are farther away from the sun and are gaseous.
11. How we compare the distance of planets from the sun and size of planets to
Earth. Explain why we do this.
 We compare distance and size in relation to Earth using Earth diameters
and Astronomical Units. We use the Earth as a reference point because it
is where we are located and the planet we know the most about.
12. Explain why Pluto is no longer considered to be a planet.
• A planet must meet the following 3 requirements in order to qualify as a
planet: It needs to be in orbit around the Sun, it needs to have enough
gravity to pull itself into a spherical shape, and it needs to have “cleared
the neighbourhood” of its orbit. Due to the small size of Pluto it does not
meet the third criteria.
13. Describe the difference between an asteroid, comet and a meteor.
•
•
•
Asteroids: Rocks floating in space. These can range in size from 1m to
hundreds of km.
Comets are made up of ice and dust and orbit the sun at large distances.
Rock fragments that burn up on entry into Earth’s atmosphere, producing
enough light to be seen are meteors.
14. Explain why in Nova Scotia we have 4 distinct seasons.
 Nova Scotia has distinct seasons due to where we are located in
relation to the equator. We are north of the equator so we do not
get direct sunlight all of the time.
 During our summer months we are tilted towards the sun so we
receive more direct sunlight.
 During our winter months we are tilted away from the sun so we
receive less direct sunlight.
 Our fall and spring seasons are the transition between being tilted
towards and away from the sun.
15. What are the main aspects of our Earth that affect the seasons.
 The Earth is round. Sunlight travels in straight lines so it hits parts of the
Earth directly giving the maximum amount of heat. Where the Earth hits
indirectly there is less heat as the same amount of heat has to heat up a
larger area.
 The Earth is tilted. This means that at certain times of the year parts of
the Earth are tilted towards the sun and parts are tilted away from the
sun.
 The Earth revolves around the sun, placing certain areas in direct sunlight
at certain times of the year.
16. Explain why locations at the middle of the Earth (equator) are hotter than
those areas near the poles.
 The middle of the Earth (equator) is always in direct sunlight so it always
receives the most heat.
17. When does a hemisphere experience summer? Winter?
 Summer; when it is tilted towards the sun.
 Winter; when it is tilted away.
18. Explain the significance of the summer and winter solstices and spring and
fall equinox. Why did they choose the specific days?
 Fall and Spring equinox ‘s occur on the days that have exactly 12 hours of
sunlight and 12 hours of night.
 The winter and summer solstices occur on the shortest and longest days
of the year.
 It is related to the degree of tilt towards or away from the sun.
19. Explain the evolution of the Earth using the Big Bang Theory.
• It states that the universe began forming 15 to 20 billion years ago,
following an enormous explosion.
• The dust and gas created as a result of the explosion were drawn
together by gravitational attraction to form a huge cloud.
• The debris in this gigantic swirling cloud began to gather in circular
movements called eddies.
• The largest eddies contained enough matter to form whole galaxies.
20. Why do we see light from the moon?
 Reflection of the light from the sun
21. How long is a lunar cycle?
 29.5 days
22. Explain why we see changes in the shape of the moon. Is the moon really
changing shape?
 The moon travels around the Earth, as the Earth travels around the Sun.
The moon appears to change shape because the illuminated part of the
moon is the part of the moon that reflects the light from the sun. The
Earth’s shadow blocks a portion of the sun’s light depending on where the
moon and the Earth are in their rotation.
 This gives the impression that the moon is changing shape when in reality
it is not the shadow from the Earth is changing.
23. List, draw and describe the stages of the moon.
 New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon,
Waning Gibbous, Last Quarter, Waning Crescent
24. Define: Waxing, Waning, Crescent and Gibbous.
 Waxing: Getting Bigger, Waning: Getter smaller
 Crescent: Less than half, Gibbous: More than half
25. When we see a full moon what stage of the lunar cycle it the moon in?
 The moon is half way through the lunar cycle. We only see the half of he
moon that is illuminated.
26. What is a star?
 A star is a luminous globe of gas producing its own heat and light by
nuclear reactions (nuclear fusion).
27. What does the brightness of a star depend on?
 The size and closeness to Earth
28. What does the colour of a star indicate? Describe a blue star.

The colour of a star indicates the temperature. Red stars are cool, yellow
hotter, blue stars are hot and white stars are the hottest.
29. Describe the life cycle of each type of star. (You can use a diagram to help)
 Nebula  Low Mass Star  red Dwarf  White Dwarf
 Nebula  Intermediate Mass Star  Red Giant  White Dwarf
 Nebula  Massive Star  Supergiant  Supernova
30. Describe a supernova.
 This is the explosive death of a star, and often results in the star obtaining
the brightness of 100 million suns for a short time.
 Supernovas cause neutron stars and black holes.