eQuizShow

Grade 9 Science Review

Chemistry

Question:

Is salt water a mechanical mixture, solution, suspension, colloid or pure substance?

Answer:

Salt water is a solution.

Question:

Is water a pure substance or a mixture. Explain why.

Answer:

Water is a compound as it is comprised of two elements (H and O) chemically attached together.

Question: What is the ratio of gases produced from the electrolysis of water?
Answer: Two parts hydrogen to one part oxygen.

Question: Which element has more protons, helium or carbon?
Answer: Carbon

Question: How many atoms are in this compound?
NH₄NO₃
Answer: 9

Ecology

Question: Which of Canada's major biomes has the shortest growing season? (Choose from tundra, grassland, boreal forest or temperate deciduous forest).
Answer: tundra

Question: At which of the following trophic levels would you find a herbivore? (producer, primary consumer, secondary consumer, tertiary consumer)
Answer: primary consumer

Question: Which type of relationship occurs between two organisms of different species that live together, when both benefit from the relationship?
Answer: mutualism

Question: What are invasive species? Describe on method of controlling the spread of invasive species.
Answer: Organisms that are not native to the ecosystem. They can be controlled by mechanical control (removing the organisms by hand), chemical control (applying pesticides), biological control (applying predators to the species) etc.

Question: Compare natural and synthetic fertilizers.
Answer: Natural
- slow and consistent release of nutrients
- can improve the structure of the soil
- materials derived from living things
- eg. manure

Synthetic
- release nutrients very quickly
- have a high concentration of nutrients
- made from synthetic chemicals
- eg. ammonium sulfate

Electricity

Question:

Which piece of equipment is used to measure the potential difference in a circuit?

Answer:

voltmeter

Question: How can you remove a charge from an object. Name and explain the process.
Answer: Ground it. Connect it directly to the earth.

Question: A circuit is connected with three identical loads. The potential difference at each load is identical. Is this circuit set up in series or parallel?
Answer: parallel

Question: In a series circuit, three 4 ohm bulbs are used. What is the total resistance?
Answer: 12 ohms

Question: What is the definition of current?
Answer: The amount of charge that passes a point in a wire every second.

Space

Question: Place these stars in order from hottest to coldest: blue, red, yellow
Answer: blue, yellow, red

Question: How is the energy in the sun produced? Give the name of the process and describe it.
Answer: Nuclear fusion.
Hydrogen fuses to helium, releasing energy in the reaction.

Question: How can astronomers deduce what a star is made of?
Answer: Spectrograph analysis. The star's spectrum will show dark lines where the different gases are absorbed.

Question: When a star explodes in a supernova, what is formed? Give the two possibilities and explain what determines which possibility.
Answer: Black hole or neutron star. It is determined by size. Very large stars (greater than 30 solar masses) will form black holes and large stars (approx. 10-30 solar masses) will form a neutron star.

Question: Where would our Sun be found on a H-R diagram?
Answer: Middle of main sequence.

All mixed up

Question: What is the largest planet and the smallest planet in our solar system?
Answer: Largest - Jupiter
Smallest - Mercury

Question: How many neutrons are in a sodium atom?
Answer: 12 (atomic mass of 23- atomic number of 11)

Question: If an object has a deficiency of electrons, will it have a positive or negative charge.
Answer: positive

Question: What is bioremediation?
Answer: Bioremediation is the use of micro-organisms to clean up environmental pollutants.

Question: Compare the properties of metals to non-metals. Include an example for each.
Answer: Metals
- shiny lustre, conduct electricity, malleable and ductile
- eg. Mg, Na
Non-metals
- dull, poor or non-conductors, brittle,
- eg. O, C