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Of 67 the Diagrams Show Two Different Models of an Atom. 'Plum Pudding'

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Q1. The diagrams show two different models of an atom. ‘Plum pudding’ model Model used today (a) The particles labelled ‘Xߣ in the plum pudding model are also included in the model of the atom used today. What are the particles labelled ‘X’ ? _________________________ (1) (b) Scientists decided that the ‘plum pudding’ model was wrong and needed replacing. Which one of the following statements gives a reason for deciding that a scientific model needs replacing? Tick ( ) one box. The model is too simple. The model has been used by scientists for a long time. The model cannot explain the results from a new experiment. (1) (c) The table gives information about the three types of particle that are in the model of the atom used today. Page 1 of 67 Particle Relative mass Relative charge 1 +1 very small –1 1 0 Complete the table by adding the names of the particles. (2) (Total 4 marks) Q2. (a) The diagram represents an atom of beryllium. Use words from the box to label the diagram. electron ion isotope molecule nucleus (2) (b) Use crosses (x) to complete the diagram to show the electronic structure of a magnesium atom. The atomic (proton) number of magnesium is 12. (2) (Total 4 marks) Page 2 of 67 Q3. The diagram represents an atom. Choose words from the list to label the diagram. electron ion neutron nucleus (Total 3 marks) Q4. About 100 years ago a scientist called J. J. Thomson thought that an atom was a ball of positive charge with negative particles stuck inside. Today a different model is used. The diagram shows how an atom of carbon is represented by this model. (a) The negative particles are called electrons. (i) What is the name of the positive particles ? ______________________________________________________________ (1) (ii) What particle is represented by ●? Page 3 of 67 ______________________________________________________________ (1) (iii) What is the central part of the atom called that contains both and ●? ______________________________________________________________ (1) (b) Use the model to explain why the six electrons are arranged as shown. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (2) (Total 5 marks) Q5. Lithium is a very reactive metal. (a) Lithium reacts with cold water. (i) Which physical property of lithium is seen during this reaction? ______________________________________________________________ (1) (ii) Which chemical property of lithium will be shown by the universal indicator? ______________________________________________________________ (1) (b) Complete the sentence by writing in the missing numbers. Lithium has an atomic number of 3 and a mass number of 7. This means that an atom of lithium has __________ protons __________ electrons and ____________ neutrons. Page 4 of 67 (3) (Total 5 marks) Q6. The diagram shows a light bulb. (a) (i) An argon atom has the structure shown. Use the words in the box to label the particles in the atom. Each word should only be used once. electron neutron proton (2) (ii) Argon is unreactive. Why? ______________________________________________________________ ______________________________________________________________ (1) (b) Oxygen would not be a suitable gas to use in a light bulb. Explain why. ___________________________________________________________________ ___________________________________________________________________ (2) (Total 5 marks) Q7. Page 5 of 67 The diagram represents an atom of lithium. (i) Complete the diagram by writing in the spaces the name of each type of particle. Use only words given in the box. Each word may be used once or not at all. electron neutron nucleus proton (3) (ii) Which type of particle found inside the atom is uncharged? ___________________________________________________________________ (1) (iii) What is the mass number of this atom, 3, 4, 7 or 10? ___________________________________________________________________ Give a reason for your choice. ___________________________________________________________________ ___________________________________________________________________ (2) (Total 6 marks) Q8. The diagrams show the electronic arrangement of the atoms of two elements. Page 6 of 67 (i) Name the part of the atoms labelled X. ___________________________________________________________________ (1) (ii) Why are these two elements in the same group of the Periodic Table? ___________________________________________________________________ ___________________________________________________________________ (1) (Total 2 marks) Q9. The diagram represents the electronic structure of an atom of an element. The periodic table on the Data Sheet may help you with this question. (a) Name this element. ______________________________________________________________ (1) (b) Complete this sentence. The nucleus of an atom contains neutrons and _________________________ . (1) (Total 2 marks) Q10. John Dalton wrote these statements in 1808. • “All substances are made of a vast number of extremely small particles called atoms.” • “Every particle of water is like every other particle of water, every particle of hydrogen is like every other particle of hydrogen, etc.” (a) “Every particle of water is like every other particle of water.” Use Dalton’s ideas and your knowledge of water to explain why. Page 7 of 67 ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ (2) (b) Dalton thought that all atoms of an element are exactly the same. We now know that it is possible to have atoms of the same element but with different mass numbers. The diagrams represent two atoms of hydrogen. Atom A Atom B State, in terms of particles, how these two atoms are different. ______________________________________________________________ ______________________________________________________________ (1) (Total 3 marks) Q11. Figure 1 represents an atom of sulfur. Figure 1 (a) Complete the table below. Number of particles in a sulfur Particle atom Electron 16 Neutron Proton 16 (1) (b) Sulfur is in Group 6 of the periodic table. Complete the electronic structure of the sulfur atom represented in Figure 2 Figure 2 Page 8 of 67 (1) (c) Sulfur reacts with oxygen to produce sulfur dioxide. Complete the word equation for this reaction. sulfur + ____________________________________________________________ (1) (d) What effect is caused by sulfur dioxide? Tick one box. Acid rain Global dimming Global warming Sea levels rising (1) (e) Figure 3 shows the mass of sulfur dioxide in the Earth’s atmosphere between 1984 and 2014 Figure 3 Page 9 of 67 A student said: ‘the mass of sulfur dioxide in the atmosphere decreased every year between 1984 and 2014’ Is the student correct? Use data from Figure 3 to justify your answer. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ (3) (f) Figure 4 shows the percentage of sulfur dioxide released by human activities. Figure 4 Page 10 of 67 Calculate the percentage of sulfur dioxide released by industry. ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ Percentage = ________________________ % (2) (Total 9 marks) Q12. The diagram represents an atom of beryllium. Use a number from the box to complete each sentence. 4 7 9 12 (a) The atomic number (proton number) of this atom is . Page 11 of 67 (1) (b) The mass number of this atom is . (1) (Total 2 marks) Q13. Two isotopes of hydrogen are hydrogen-1 ( ) and hydrogen-2 ( ). The diagrams represent atoms of hydrogen-1 and hydrogen-2. (a) Use the correct words from the box to complete the sentences. electrons neutrons protons (i) The positive particles, , in the nucleus of atoms are called ______________________________________ . (1) (ii) The particles with no charge, ● , in the nucleus of atoms are called ______________________________________ . (1) (b) The diagrams show two different types of water molecule. Draw a ring around the correct answer to complete the sentence. heavier than Molecule A is lighter than molecule B. Page 12 of 67 the same mass as Explain your answer. ___________________________________________________________________ ___________________________________________________________________ (2) (Total 4 marks) Q14. This question is about atoms and molecules. (a) Complete the table to show the relative masses of the particles in atoms. Name of particle Relative mass Proton ______________ Neutron 1 Electron ______________ (2) (b) The diagram shows an oxygen atom. Use the correct number to complete each sentence. 8 16 18 24 The atomic (proton) number of the oxygen atom shown above is ______________ . The mass number of the oxygen atom shown above is ______________________ . (2) (c) (i) Draw
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