Look at the measuring cylinders. What happened to the volume of the water and the wax after freezing? the volume of water... the volume of wax...

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1 1. Meera poured 7 cm 3 of water into a measuring cylinder. She poured 7 cm 3 of melted wax into another measuring cylinder. She put both measuring cylinders into a freezer for 24 hours. water before freezing cm 3 cm water after freezing wax before freezing cm 3 cm wax after freezing (a) Look at the measuring cylinders. What happened to the volume of the water and the wax after freezing? the volume of water... the volume of wax... (b) The measuring cylinders were taken out of the freezer and left in a room at 20 C. Frozen water melts at 0 C. Wax melts at 53 C. What would the physical state of each substance be at 20 C? Choose from gas or liquid or solid. water... wax... 2 marks Shire Oak School 1

2 (c) Meera added blue copper sulphate crystals to some water in a beaker. The copper sulphate dissolved in the water. blue copper sulphate crystals water before adding copper sulphate after adding copper sulphate (i) Give one way Meera could see that the copper sulphate had dissolved in the water... Give one way that she could get the copper sulphate to dissolve more quickly... (d) Meera poured some of the copper sulphate solution into a dish. She left it in a warm room for a week. copper sulphate solution A week later there was a blue solid but no liquid in the dish. (i) What happened to the water in the copper sulphate solution?.. What was the blue solid left in the dish?... maximum 7 marks Shire Oak School 2

3 2. Six groups of pupils burned magnesium in air. The magnesium reacted with oxygen to form magnesium oxide. They recorded the mass of magnesium used and the mass of magnesium oxide formed. Their results are shown in the table. group mass of magnesium (g) mass of magnesium oxide (g) A B C D E F (a) Use their results to draw a graph below. Decide the scale for each axis. Plot the points. Label the axes. Draw a line of best fit. 4 marks Shire Oak School 3

4 (b) (i) Which group s results do not fit the general pattern? Give the letter. How should the class deal with this odd result?.... (c) Use the graph to predict the mass of magnesium oxide that will be formed by burning 7.0 g of magnesium (d) The results show the relationship between the mass of magnesium and the mass of magnesium oxide formed. What conclusion could you draw about this relationship? maximum 8 marks 3. The drawings show six objects made from different materials. not to scale Shire Oak School 4

5 (a) Fill the gaps in the sentences below. The objects are made from materials that are all types of... All the materials are good conductors of electricity and... (b) From the drawings above give one object that could rust.... (c) The drawing below shows part of an electric cable and a plug. (i) What material could be put around the wires to insulate them? Why is this insulating material needed? Shire Oak School 5

6 (d) Which pair of objects is attracted to a magnet? Tick the correct box. maximum 6 marks 4. (a) Samantha opened a tin of white paint. The paint consisted of a liquid and particles of titanium dioxide that are insoluble in the liquid. The paint had separated into two layers, as shown below. liquid particles of insoluble titanium dioxide (i) What type of substance is the paint? Tick the correct box. a compound an element a mixture What type of substance is titanium dioxide? Tick the correct box. a compound an element a mixture Shire Oak School 6

7 (iii) Why did the particles of insoluble titanium dioxide sink to the bottom? (b) Samantha stirred the paint and used it to paint a window frame. She got some of the paint on the glass. Samantha could not get the paint off the glass with water. When she used a different liquid called white spirit the paint came off. Why could she remove the paint with white spirit but not with water? maximum 4 marks Shire Oak School 7

8 5. In the 19th Century, a scientist called John Dalton used symbols to represent atoms. The symbols he used for atoms of three different elements are shown below. The diagrams below show different combinations of these atoms. A B C D E (a) (i) Give the letter of the diagram which shows a mixture of two elements.... Shire Oak School 8

9 Give the letter of the diagram which shows a mixture of two compounds.... (iii) Give the letter of the diagram which shows a mixture of an element and a compound.... (b) Give one difference between a compound and a mixture (c) (i) Suggest a name and formula for the substance represented in diagram B. name... formula... Suggest a name and formula for the substance represented in diagram D. name... formula... maximum 6 marks 6. (a) The table below shows the melting points of four metals. metal melting point, in C gold 1064 mercury 37 sodium 98 iron 1540 Shire Oak School 9

10 (i) Which metal in the table has the highest melting point?... Which metal in the table has the lowest melting point?... (b) Gold can be a gas or a liquid or a solid. Choose from these words to fill the gaps below. When gold is heated from room temperature to 1070 C, the gold changes from a... to a.... (c) 5 g of gold is melted and all of it is poured into a mould to make a pendant as shown below. What is the mass of the gold pendant?... g Shire Oak School 10

11 (d) The table below shows how the four metals react with oxygen when heated in air. metal gold mercury sodium iron reaction when heated in air no change slowly forms a red powder bursts into flames straight away very slowly turns black (i) Which is the most reactive metal in the table?... Which is the least reactive metal in the table?... Maximum 6 marks 7. The diagram shows an outline of part of the Periodic Table of Elements. H region 1 region 2 region 3 (a) What is the name of the element with the symbol H?. Shire Oak School 11

12 (b) In which regions of the Periodic Table are the following types of element found? (i) non-metals (such as oxygen and chlorine); region very reactive metals (such as sodium and potassium); region (iii) less reactive metals (such as copper and zinc). Region (c) Why is copper sulphate not found in the Periodic Table?.. (d) An iron nail is placed into some blue copper sulphate solution. A reaction takes place between the iron and the copper sulphate. (i) Complete the word equation for the reaction. iron + copper sulphate + Describe one change you would see on the surface of the nail..... Maximum 7 marks Shire Oak School 12

13 8. The diagrams represent the arrangement of atoms or molecules in four different substances, A, B, C and D. A B C D not to scale Each of the circles,, and represents an atom of a different element. (a) (i) Which substance is a compound? Which substance is a mixture? (iii) Which two substances are elements? and (iv) Which two substances could be good thermal conductors? and (v) Which substance could be carbon dioxide? Shire Oak School 13

14 (b) The following experiment was set up. Test-tubes containing substances B and C were placed together as shown. The substances did not react. They were left for five minutes. test-tubes put together + mixture of substance B and substance C substance B substance C (i) How many molecules are there in the mixture compared to the total number in substances B and C?.. Complete the diagram which is a model of this experiment. + substance B substance C mixture Maximum 7 marks Shire Oak School 14

15 9. A section of the periodic table of elements is shown below. H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar (a) Where in this section of the periodic table are the metals found?... (b) Sodium chloride is formed when sodium and chlorine combine together in a chemical reaction. Write the symbols for sodium and chlorine. sodium chlorine marks (c) The formula for a substance is MgS. What is the name of this substance?... Shire Oak School 15

16 (d) Give the name of one element in the table above which is a gas at room temperature and in which the atoms are joined together in molecules.... Maximum 5 marks Shire Oak School 16

17 10. The elements in group 7 of the periodic table are known as the halogens. melting point in C boiling point in C relative atomic mass colour of element at room temperature, 20 C fluorine very pale yellow chlorine greenish yellow bromine reddish brown iodine dark grey astatine 210 (a) (i) Predict the physical state of astatine at room temperature. Predict the colour of astatine at room temperature. Tick the correct box. colourless yellow brown black (b) The reactions of chlorine and bromine with some sodium salts are given below. salt colour of salt solution colour after addition of chlorine solution, which is greenish yellow colour after the addition of bromine solution which is orange sodium chloride colourless pale greenish yellow sodium bromide colourless orange orange orange sodium iodide colourless dark brown dark brown Shire Oak School 17

18 (i) Use these observations to put the elements bromine, chlorine and iodine in order of reactivity. least reactive most reactive... A solution of iodine, which is dark brown, is added to a solution of sodium bromide. What will be the colour of the resulting solution? (c) Predict, with a reason, if there will be a reaction between: (i) fluorine and sodium chloride solution. astatine and sodium iodide solution. Maximum 6 marks 3 marks Shire Oak School 18

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