1. Put the corn in a saucepan. 2. Add some oil. 3. Put a lid on and heat the corn. 4. Add some salt.

Transcription

1 salt Level 3 1. Popcorn (a) Sasha watches her father make some popcorn. These pictures show what he does. 1. Put the corn in a saucepan. 2. Add some oil. 3. Put a lid on and heat the corn. 4. Add some salt. Use the pictures. Tick ONE box after each sentence to show if it is true or false. The pictures show that as the corn pops, it... True False gets bigger. changes to a darker colour. changes shape. gets smoother. 2 marks John Buchan Middle School 1

2 (b) After the corn is cooked it is hot. What should Sasha measure to find out how hot the popcorn is? Tick ONE box. Sasha should measure the... mass. temperature. volume. time to cook. (c) Look at the pictures above. Tick ONE box to show what is most likely to cause the corn to change. salt oil heat saucepan (d) When corn is popped, a new material is formed. This change is not reversible. Describe a different non-reversible change where another new material is formed John Buchan Middle School 2

3 2. Flames (a) Halim watches dead leaves in a bonfire. He can see smoke rising from the fire. Tick ONE box to show what the smoke is. Smoke is... liquid from evaporation. liquid from melting. new materials made by burning. new materials made by the leaves. (b) The next day, Halim s teacher holds some materials over a candle flame. Describe ONE thing in the picture that Halim s teacher has done to help make the investigation safe.... John Buchan Middle School 3

4 (c) Halim records the results in a table. Write yes or no in each row to show whether the changes are reversible. wood Material Does it burn? yes Is the change reversible? bread yes (d) Halim wants to know what other materials will burn. Tick the boxes next to all the materials below that burn in a candle flame. One has been done for you. cardboard cotton wool stone kitchen foil newspaper steel wool 2 marks John Buchan Middle School 4

5 Level 4 3. In the kitchen (a) Layla collects different objects from the kitchen. glass foil rolling pin plastic food wrap candle She looks at some of the properties of the materials these objects are made from. Write a or in each empty box in the table to show the properties of the materials. Material/Object Flexible Hard Transparent aluminium foil wax candle wooden rolling pin plastic food wrap glass (b) Aluminium foil is flexible. Give ONE use of aluminium foil in the kitchen where it is important that the foil is flexible.... John Buchan Middle School 5

6 (c) Layla knows some changes are reversible. Tick THREE boxes to show which changes are reversible. cooling water cooking bread boiling an egg mixing vinegar with bicarbonate of soda freezing water into ice burning a candle dissolving salt in water 2 marks (d) Layla watches some water boiling near a window. The picture shows what she can see on the window. (i) Write the missing label for the picture below by choosing from the words in the box below. water vapour condensation steam smoke window... John Buchan Middle School 6

7 (ii) Why does the level of the water inside the saucepan go down if the water continues to boil? Adding water (a) Safara wants to find out what happens when solids are mixed with water. She adds water to four different solids and stirs the mixtures. After 20 minutes she draws pictures of her results. colourless liquid cloudy liquid beaker A solid pieces beaker B brown solid colourless liquid coloured liquid bubble beaker C beaker D The table below names the four solids that Safara mixed with water. Which solid was in each beaker? Write A, B, C or D to complete each row of the table. Solid soil vitamin tablet plastic beads salt Beaker John Buchan Middle School 7

8 (b) Explain what happened to the solid in beaker C.... (c) In which beaker was there a non-reversible change? Beaker... (d) Safara wants to separate the soil from her mixture of soil and water. Tick ONE box to show which equipment would be best for separating the soil from the water John Buchan Middle School 8

9 (e) Safara wants to separate the salt from her mixture of salt and water. Describe how Safara could get solid salt back from the salt and water mixture Acid rain (a) Sometimes rain mixes with pollution in the air to form acid rain. Some children want to find out what happens when acid rain falls on rocks. Vinegar can be used to show the effects of acid rain. The children add vinegar to chalk rock. The pictures below show what happens. bubble vinegar dish Chalk rock Chalk rock and vinegar Bubbles are produced. Write true or false next to each sentence below. The change is non-reversible.... The bubbles evaporate.... John Buchan Middle School 9

10 (b) Write solid, liquid or gas next to each material in the table. Material Solid, liquid or gas? inside the bubble vinegar chalk rock (c) The children test more rocks. The table below shows their results. Rock granite sandstone limestone slate pumice Are bubbles produced when vinegar is added? no no yes no yes Look at these pictures of a statue. The statue is in a city that has acid rain. Statue when new Same statue after 200 years Use the table to name ONE rock that this statue could have been made from.... John Buchan Middle School 10

11 Level 5 6. Yeast (a) Yeast is a type of micro-organism. Class 6G know that bread needs yeast to rise. The yeast must be mixed with water and sugar. They want to find out if the temperature of the water affects the yeast. They put sugar in a bottle and add water at a temperature of 20 C. Name the scientific word that describes what happen to the sugar when it is mixed with water.... (b) The class then add yeast to the sugar and water in the bottle. They put a balloon over the top of the bottle. They time how long it takes for the balloon to stand up. Write true or false next to each statement about the investigation. True or false? A gas is produced by the yeast.... A reversible change has happened.... The balloon is flexible.... John Buchan Middle School 11

12 (c) The class repeat the test using water at different temperatures. The teacher adds the same amount of yeast, sugar and water each time. The table below shows their results. Temperature of water (ºC) Time taken for balloon to stand up (mins) Describe how the temperature of the water affects the time taken for the balloon to stand up marks (d) A cook book says that yeast works most quickly with water at a temperature of 20ºC to 30ºC. (i) Tick ONE box to show if the results in the table support the information in the cook book. yes no (ii) Use examples from the results table to help you explain your answer John Buchan Middle School 12

13 7. Burning Candles (a) Dianne put a wax candle on some scales. The teacher lit the candle and left it to burn. Dianne noticed a liquid around the bottom of the wick. What is this liquid?... John Buchan Middle School 13

14 (b) Write the name of the process when a solid turns to a liquid.... (c) Dianne measured the mass of the candle every 30 minutes. Her results are shown on this graph. Look at the graph. What happened to the mass of the candle while it was burning?... (d) Gareth said, When the candle wax burns, the change can be reversed. Dianne did not agree with him. She said, This change is irreversible. Explain why Dianne is correct John Buchan Middle School 14