Grade 9 Science Review (Part 2)


Question: This planet has a thick cloud cover, making it the hottest planet.
Answer: Venus

Question: This planet has the most distinctive rings.
Answer: Saturn

Question: What is a white dwarf?
Answer: A small, hot star that is not very bright. It is formed near the end of the lifecycle of an intermediate mass star.

Question: What is an astronomical unit?
Answer: The distance from the Earth to the Sun. (Approximately 150 000 000 km)

Question: Name three year round constellations.
Answer: Big Dipper (Ursa Major), Little Dipper (Ursa Minor) and cassiopeia.


Question: Which terrestrial biome has the highest biodiversity?
Answer: tropical rainforest

Question: Which element is found in large amounts in fossil fuels, the ocean, limestone and plants?
Answer: Carbon

Question: Describe three methods of improving soil fertility.
Answer: Crop rotation - changing the location of monocultures each year
Fertilizers - adding chemicals to the soil
Manure - adding animal waste to the soil
Green manure - ploughing plants under instead of harvesting

Question: Explain the difference between physical and chemical properties. Give two examples for each.
Answer: Physical properties - properties that can be described without the formation of a new substance (Eg. colour, hardness, odour, mass)
Chemical properties - properties that describe how a substance reacts with another. (eg. combustibility, reaction with water, reaction with acid)

Question: Explain the difference between clear cutting, shelterwood cutting and selective cutting.
Answer: Clear cutting - removal of all or most of the trees
Shelterwood - mature trees are harvested in a series of two or more cuts
Selective cutting - removes selective trees to keep the forest in a multi-aged system



A homogeneous mixture of one or more metals is called an:




List the two elements on the periodic table that are liquids at room temperature. Which is a metal and which is a non-metal?


Metal - mercury
Non-metal - bromine


What is a precipitate?


A solid produced when two liquids are reacted together.


During an experiment, you mix two chemicals together and a gas is produced. Describe how you could test if this gas is oxygen, hydrogen or carbon dioxide.


Oxygen - glowing splint with re-light
Hydrogen - blazing splint will make a "pop" sound
Carbon dioxide - blazing splint will go out or limewater will turn cloudy


Explain how to draw a Bohr diagram.


Find the number of protons from the atomic number on the periodic table.
Find the number of neutrons by subtracting the atomic number from the atomic mass.
Place the electrons around the nucleus in the correct orbitals. (2,8,8)


Question: Explain the difference between a series and parallel circuit.
Answer: In a series circuit, the electrons flow along one path. In a parallel circuit, the electrons flow along more than one path.

Question: Explain the difference between a conductor and an insulator. Give an example for each.
Answer: A conductor allows electrons to flow through it easily (eg. copper wire or silver spoon). An insulator does not allow electrons move move through it very easily (eg. rubber or wood)

Question: Describe which device must be used to measure current and which device is used to measure potential difference. Explain how to connect each in a circuit.
Answer: Current - ammeter connected in series
Potential difference - voltmeter connected in parallel

Question: Use an example to explain the difference between atomic number and atomic mass.
Answer: The atomic number tells you the number of protons in the atom. The periodic table is organized by atomic number.
The atomic mass tells you the number of protons and neutrons in the atom.

Question: Describe the three methods for creating a static charge on an object.
Answer: Friction - rub the two materials together. The one with a stronger attraction for electrons become negative and the one with a weaker attraction will lose electrons and become positive.

Conduction (Contact) - Touch a charged object to a neutral object. The same charge will be transferred.

Induction - A temporary charged is placed on an object when a neutral object is placed near a charged object.

All mixed up

Question: List the planets in order from the sun.
Answer: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune

Question: What is a load?
Answer: A load is any device that draws current from a circuit.

Question: What is leaching?
Answer: Leaching is the loss of water soluble nutrients from the soil.

Question: What is a spinoff?
Answer: A spinoff is a technology converted to an everyday use.

Question: What is sustainability?
Answer: Sustainability is the ability to meet the needs of the present generation without compromising the ability of future generations to meet their needs. It is maintaining an ecological balance.