Download 1 Science 9 Review 1. Metals are shiny, ductile, good conductors

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Science 9 Review
1. Metals are shiny, ductile, good conductors of heat and electricity, and malleable.
Transition metals have all of the same properties as metals, however their
electrons are arranged differently in the energy levels around the atom.
Non-metals are dull, poor conductors of heat and electricity, brittle, and not ductile.
Metalloids can by shiny or dull, can conduct electricity, are poor conductors of heat, and
are brittle and not ductile.
2. Recognizing: Ionic compounds have 1 metal and 1 or more nonmetals in them. Covalent
compounds have 2 or more nonmetals.
Naming: For ionic compounds, you write the name of the metal, and then the name of the
nonmetal with the end changed to “ide”. For example, NaCl:
Na = sodium Cl = chlorine... need to change the end... chlorine= chloride
The compound name is sodium chloride. You don’t need to worry about numbers
with ionic compounds. For example, Li3N...
Li = lithium
N=nitrogen... need to change the end... nitrogen=nitride
(usually you cut off after the “r” in the nonmetal name).
The compound name is lithium nitride.
For covalent compounds, you need to look at how many of each element (nonmetal) there
are, as well as what the elements are. You write the full name of the first element in the
compound, and change the end of the second element. You use prefixes for the numbers.
For example, Cl3H6.
Cl= chlorine. There are 3, so the prefix is tri... trichlorine
H= hydrogen... need to change the end... hydrogen=hydride. There are 6, so the
prefix is hexa... hexahydride.
The compound name is trichlorine hexahydride.
Covalent compounds are also sometimes called molecules (i.e. molecules are
compounds made up of nonmetals).
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3. Electron shells/energy levels are the same thing. They are the area around the nucleus
of the atom and have the largest volume of any part of the atom. They also have the
smallest mass of any part of the atom. The electrons are found there. The first energy
level can hold up to 2 electrons. The 2nd and 3rd energy levels can hold up to 8 electrons.
Ex:
Na
11p+
12n
Protons and neutrons are
found in the nucleus of the
Because a sodium atom
atom. Protons have a
has 11 protons, it has 11
positive charge, neutrons
electrons. These fall into
have no charge. Electrons
the three energy levels
are found in the energy
in the order 2, 8, 1.
levels around the nucleus
and have a negative
charge.
A Bohr-Rutherford model of this diagram would
look like this:
1e8e2e-
In these diagrams, the energy levels are
represented as lines
4. When fruit ripens/rots, it is a chemical change. There are physical properties that tell
you that the change is chemical, but the change itself is chemical because there is a
change in the molecules that make up the fruit. You know this by looking at the evidence of
a chemical change: heat, light, or sound produced; bubbles forming (gas produced);
precipitate forming; colour change; & difficult to reverse.
When fruit rots/ripens, there is a colour change and it is very difficult to reverse. This is
because there has been a change in the chemical makeup of the fruit. When fruit rots it
releases ethylene gas.
5. Corrosion is what happens when metals combine with oxygen. Rust is when corrosion
occurs with iron and water.
WHMIS
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6. There are several different atomic theories:
7. Chemical/physical changes: Chemical changes are a change in the chemical makeup of a
substance. Physical changes are changes in the appearance of a substance that do not
change what it’s made up of. Evidence of these changes are:
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8. Periodic table:
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Chem
1
2
18
13 14 15 16 17
All elements to the left of the staircase
are considered metals.
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The periodic table shows all of the
known elements. The table is arranged
in a specific way:
3 4 5 6
7 8
9 10 11 12
All elements to the right of the staircase
are considered nonmetals.
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Elements around the staircase (except
aluminum and polonium) are
metalloids.
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The vertical (up & down) columns on
the table are groups (families).
Elements in the same group will share
characteristics.
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The horizontal (left to right) rows are
the period. The higher the period
number, the more reactive an element
in a group (family) is.
Group (family) 1 = alkali metals (1 valence electron)
Group 2 = alkaline earth metals (2 valence electrons)
Groups 3-12 = transition metals
Group 17 = halogens (7 valence electrons)
Group 18 = Noble/Inert gases (2 [He] or 8 valence electrons)
The groups and period help you to find
elements, like coordinates on a map.
9. Chemical/Physical Properties.
Physical properties are observable or measurable. Chemical properties have to do with
how a substance behaves.
Qualitative Properties (Observable)
Quantitative Properties (Measurable)
Chemical properties:
1) Reactivity – How well a substance combines chemically (reacts) with other substances
2) Combustibility – How well a substance burns – how well it reacts with air or pure
oxygen
3) Toxicity – Whether or not a substance reacts with the body to produce a harmful
substance(s) – ex: lead, carbon monoxide.
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10. Alkali metals/alkaline earth metals: Alkali metals are in group (family) 1. They are
extremely reactive with air & water and they combine with nonmetals to make chemical
compounds. All of the alkali metals melt below 200oC, and all are soft enough to be cut with
a knife. Alkali metals have 1 valence electron.
Alkaline earth metals are in group (family) 2. These are less reactive than alkali metals.
They will burn in the air if they are heated (remember magnesium from the lab). They will
react with water, but not as explosively as alkali metals. Alkaline earth metals have 2
valence electrons.
11. Chemical Bonds: chemical bonds hold two or more atoms together. Ionic bonds are
formed between a metal and one or more nonmetals, and happen when metals lose
electrons. Covalent bonds are formed between 2 or more nonmetals and happen when
electrons are shared between the atoms in the bond.
12. Celestial bodies are any natural object in space (the Sun, moons, planets, comets,
asteroids, etc).
13. Constellations are groups of stars that form a pattern.
14. Dwarf planets are celestial bodies that do not have enough mass/gravitational pull to
clear their orbits of debris, but that are large enough to have a spherical shape.
15. Asteroids are pieces of rock left over from the early solar system. Most are found
between the orbits of Mars and Jupiter. Meteors are pieces of rock broken off from
asteroids. Meteoroids are small and burn up coming through the Earth’s atmosphere.
Meteorites are large enough that they do not completely burn up and will land somewhere
on Earth. Comets are dirty snowballs that orbit the sun. They have tails when they are
close to the Sun because the heat from the Sun partially melts the ice.
16. Probes are unmanned space crafts sent to other celestial bodies to gather information.
They can fly past, orbit, or land on these bodies. All of the planets in our solar system
have been visited by a probe, and a recent probe sent to Pluto is set to arrive in 2015.
Probes send images and information directly back to the Earth.
17. Rovers are like the ROVs that we learned about last year, only designed for outer
space rather than the bottom of the ocean. Rovers have highly specialized programming so
that they can problem solve and are designed to withstand extreme temperatures
(freezing cold to blistering heat). They are designed to work all day long and conserve
battery power at night.
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19. Early models of the universe.
20. Standing on the shoulders of giants.
Kepler worked with a man named Brahe. They watched the planet Mars for weeks and tried
to work out a model for how it moved. They found that a spherical orbit didn’t help to
explain Mars’ movement. When they tried an elliptical orbit, everything fell into place.
Based on his work, Kepler developed 3 laws of planetary motion:
1. All planets move around the Sun in ellipses.
2. When a planet gets closer to the Sun it speeds up, when it’s further away it slows
down.
3. The time a planet takes to revolve around the Sun is in direct proportion to how far
away it is from the Sun (i.e. Mercury will orbit the fastest, Neptune/Pluto the
slowest – depending on which one is considered the last “planet”).
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Newton was the first to show that the force of gravity extends past the surface of the
Earth, and that it affects all celestial bodies, causing them to orbit larger celestial
bodies (moons around planets, planets around the Sun, etc).
Newton invented the reflecting telescope (using mirrors & lenses instead of just
lenses).This allowed the telescope to be larger in size and give more exact images.
Astrolabes are used to show how the sky looks at a specific place at a given time. This is
done by drawing the sky on the face of the astrolabe and marking it so positions in the
sky are easy to find. To use an astrolabe, you adjust the moveable components to a
specific date and time. Once set, much of the sky, both visible and invisible, is
represented on the face of the instrument. This allows a great many astronomical
problems to be solved in a very visual way. Typical uses of the astrolabe include finding
the time during the day or night, finding the time of a celestial event such as sunrise or
sunset and as a handy reference of celestial positions.
Stone Circles: Stone circles are found all over the world, although most are in Europe.
Archaeological evidence indicates that in addition to being used as places of burial, the
purpose of stone circles was probably connected to agricultural events, such as the
summer solstice. Although no one knows for sure why these structures were built, many of
them are aligned with the sun and moon, and form complex prehistoric calendars. Although
we often think of ancient peoples as being primitive and uncivilized, clearly some
significant knowledge of astronomy, engineering, and geometry was needed to complete
these early observatories.
21. Evolution of stars:
Neutron Stars
High Mass Stars
Red Supergiants
12x or more the
Black Holes
mass of our sun.
Burn out quickly.
Intermediate Mass Stars
Low Mass Star
Red giants
Red giants
Supernova into
Shrink into
Nebula
White dwarves
22. Solar wind occurs when charged particles are ejected from the Sun. The Earth’s
magnetic field protects us from most of these particles. Those that do reach the
Earth react with gases in the atmosphere to create the Northern and Southern lights.
23. Kuiper Belt is found past Neptune’s orbit and is thought to be where short-period
comets come from.
24. Solar radiation is experienced on Earth as Sunlight. In space, solar radiation is not
blocked by our atmosphere so it could quickly cause sunburn, melanoma and radiation
poisoning.
25. Galaxies: An elliptical galaxy is a galaxy with a spherical to an elliptical shape that
contains some of the oldest stars in the universe. Some look like a baseball, some like a
football, some like a cigar. The largest galaxies in the universe are elliptical. Spiral
Galaxies: Galaxies made with long arms that spiral out from each other from a centre
core. The Milky Way is a spiral galaxy.
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26. Quasars and black holes.
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Quasars: a region of extremely high energy that develops as the supermassive
black hole in the centre of a galaxy attracts more matter into itself.
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Black Holes: a large sphere of incredibly tightly packed material with a huge
gravitational pull created when a star collapses on itself. Nothing, not even light,
can escape the gravitational field. Because of this, not one knows what they look
like.
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28. Big bang theory: The theory states that about 13.7 billion years ago, a tiny volume of
space suddenly and rapidly expanded into a gigantic size. In a short time, all matter and
energy in the universe was formed. The theory was first proposed by Georges Lemaître in
1927. The temperature of the Big Bang was over 1 000 000 000 oC. The universe has been
cooling ever since.
Oscillating theory: Oscillating theory states that not only did the universe undergo a Big
Bang, but that it will also someday undergo a Big Crunch. The idea is that the universe is
closed and that there is enough matter to eventually stop the expansion of the universe,
and through gravitational force, reverse it. This is in contrast to open universe theories
(like the Big Bang theory) which state that the universe is expanding and that the rate of
expansion is increasing (getting faster) over time.