WA2 Practice Paper: Weighted Assessment 2 — question paper

Section A: Multiple-choice questions[10 marks]

Answer all questions. For each question, write the letter (A, B, C or D) of the correct answer in the brackets provided.

1. 1

   Which substance is a compound?

   1. Apure water
   2. Bair
   3. Ciron filings
   4. Dsea water
   ( )
2. 2

   A student wants to compare the dyes in three black marker pens. Which technique should she use?

   1. Afiltration
   2. Busing a magnet
   3. Cpaper chromatography
   4. Devaporation to dryness
   ( )
3. 3

   A ray of light passes from air into a glass block and bends towards the normal. What is this called?

   1. Areflection
   2. Brefraction
   3. Cdiffusion
   4. Dconduction
   ( )
4. 4

   Which list contains only elements?

   1. Awater, salt and sugar
   2. Bair, brass and sea water
   3. Ccarbon dioxide, rust and glass
   4. Dcopper, oxygen and iron
   ( )
5. 5

   Sand is stirred into water. Which method collects the sand as a residue?

   1. Afiltration
   2. Bsimple distillation
   3. Cpaper chromatography
   4. Dusing a magnet
   ( )
6. 6

   The angle of incidence is the angle between the incident ray and which line?

   1. Athe mirror surface
   2. Bthe reflected ray
   3. Cthe normal
   4. Dthe edge of the glass block
   ( )
7. 7

   Sugar dissolves in water to form a solution. In this solution the sugar is the

   1. Asolvent
   2. Bsolute
   3. Cresidue
   4. Dfiltrate
   ( )
8. 8

   A ray hits a plane mirror. The angle of incidence is 35°. What is the angle of reflection?

   1. A55°
   2. B70°
   3. C145°
   4. D35°
   ( )
9. 9

   Which technique collects the liquid solvent from a salt solution?

   1. Asimple distillation
   2. Bfiltration
   3. Cmagnetic attraction
   4. Dpaper chromatography
   ( )
10. 10

    Brass is made by mixing copper and zinc. Brass is

    1. Aa compound
    2. Ban element
    3. Ca mixture
    4. Da single kind of atom
    ( )

Section B: Structured questions[20 marks]

Answer all questions in the spaces provided. Show your working for calculations.

1. 1

   A bottle is labelled “sodium chloride”. A second bottle contains salty sea water.

   1. (a)

      State whether sodium chloride is an element, a compound or a mixture.

      [1]
   2. (b)

      Give one reason for your answer to (a).

      [1]
   3. (c)

      Sea water is a mixture. State two differences between a compound and a mixture.

      [2]
   4. (d)

      Name the solvent in sea water.

      [1]
2. 2

   A mixture contains iron filings, sand and salt dissolved in water.

   1. (a)

      Describe how to remove the iron filings first.

      [1]
   2. (b)

      The remaining mixture is filtered. State what is left on the filter paper and what is in the filtrate.

      [2]
   3. (c)

      Describe how to obtain dry salt crystals from the filtrate.

      [2]
3. 3

   A ray of light hits a plane mirror. The normal is drawn at the point where the ray meets the mirror.

   1. (a)

      State the angle between the normal and the mirror.

      [1]
   2. (b)

      The angle of incidence is 40°. State the angle of reflection and the law you used.

      [2]
   3. (c)

      A student measures the angle of incidence from the mirror surface instead of from the normal, and writes 50°. Explain his mistake.

      [2]
4. 4

   A ray of light travels from air into a rectangular glass block.

   1. (a)

      The ray bends towards the normal as it enters the glass. State whether the angle of refraction is larger or smaller than the angle of incidence.

      [1]
   2. (b)

      The ray leaves the opposite face of the block and goes back into air. State what happens to its direction, and why.

      [2]
   3. (c)

      State two properties of light that the ray model uses.

      [2]