Grade 5 Chemistry Test

Grade 7 Chemistry test 11

Name _______________________________________ Class:____

Answer all questions clearly, and rub out any errors properly please. You may use your notebooks in this test if you wish.

1. This question is about water quality. (11 marks in total)

a) Why is it important that water quality is monitored ?

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(2 marks)

b) What things about the water can be measured?

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(3 marks)

c) If you analysed a sample of water from a Lapland lake and one sample from the sea near Kemi, how do you think they would they be different ? Describe and explain the differences carefully.

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d) A wealthy Japanese company builds a paper mill (paperitehdas) 10km north of Oulu.

If you were a scientist monitoring the water quality in the area, what changes might you expect because of this ? Explain your answer.

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(3 marks)

2.This question is about separating mixtures. (6marks in total)

Susie used her science knowledge to identify the coloured substances in the ink from a felt-tip pen. She used 4 samples:

green ink blue ink purple ink ink from her felt-tip pen.

She used water to dissolve the ink. Look at the diagram on the next page carefully

(a) What is the name of this type of experiment …………………………………………………… 1 mark

(b)(i)Which colours were present in the ink from the felt-tip pen?

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(ii) How many coloured substances were there in green ink? ……………….

How can you tell?

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(iii)Susie placed the spots of ink on a line on the paper as shown in the diagram.
To draw the line, Susie had to choose a felt-tip pen or a pencil. Which one should she use? Give the reason for your answer.

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(c) Susie used water as the solvent in this experiment. When she repeated the experiment with a different set of pens, it did not work. She then used ethanol instead of water and it worked.

Suggest why the experiment worked with ethanol but not with water.

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3. This question is about making tea. (15 marks in total)

a) Is making tea a chemical or physical change ? ……………………………………………………………..

b) At what temperature should the water boil ? ……………………………………………………………….

c) On the diagram, carefully label one place in which you see each of the i) solvent ii) solute iii) solution.

d) Is the finished drink an element, mixture or compound ?...................................................................

e) Explain your answer to d) …………………………………………………………………………

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f) If the teabag breaks, what could you do to the tea drink to make it more pleasant to drink ? …

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g) Draw a correctly labelled diagram to show how you would do this.

4. This question is about fire safety.

Elias is cooking makkara at a forest fireplace (nuotio). He drops his sausage and it is burning in the middle of the grill plate. Using the idea of the fire triangle, describe three ways that he can put out the fire. (4 marks)

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5. This question is about diagrams (6 marks in total)

In each of the diagrams/pictures, explain what is wrong with the way they are drawn. To the right of each, draw the correct diagram

a) beaker

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b) empty test tube

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c) water in a measuring cylinder

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