Section A[60 marks] Answer All questions in this section. The time suggested to complete Section A is 90 minutes. 1. Figure 1 shows a graph of temperature againt time of subtance Z when it is heated until it boils. Figure 1 (a) state the physical state of Z at the region (i) PQ : _________________ (ii) QR : _________________ (iii) RS : _________________ (iv) ST : _________________ (v) TU : _________________ [3 marks] (b) Describe the movement of the particles of the pure substance at stage PQ of the curve ? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ [2 mark] (c) Draw a diagram to show the arrangement of particles of the subtance at stage QR in the box below. [2 marks] (d) What is the time when the Z begins to boil ? ______________________________________________________________ [1 mark] (e) What is the melting point of Z ? ______________________________________________________________ [1 mark] (f) Explain why the temperature of Z remains constant from time t 1 to t2 ? ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ [2 marks] (g) Sketch the graph obtained when molten Z is cooled from 460 0C to room temperature. . [2 marks] 2. Y and Z. (a) Write the electron arrangements of all the particles in Table 1. Particle V W X Y Z Proton number 6 8 8 11 16 Nucleon number 12 16 18 23 32 Electron arrangement Table 1 Table 1 shows the proton number and nucleon number of five particles represented by the letters V. W. X. ______________________________________________________________ [1 mark] (e) Explain the meaning of nucleon number. [2 marks] (d) State the number of electron shells in particles Z. ______________________________________________________________ ______________________________________________________________ [1 mark] (f) What is the number of neutrons in particle Y ? ______________________________________________________________ [1 mark] (g) (i) Explain the meaning of the term ‘isotope’ ______________________________________________________________ ______________________________________________________________ [2 marks] (ii) State a pair of isotopes from the particles in Table 1.[2 marks] (b) What is the number of valence electrons in particle V? ______________________________________________________________ [1 mark] (c) Draw the atomic structure of particle Y. ______________________________________________________________ [1 mark] . Mass of heating tube + asbestos paper Mass of heating tube + asbestos paper + contents before heating Mass of heating tube + asbestos paper + contents after heating 24. Pb. ______________________________________________________________ ______________________________________________________________ [2 marks] (b) How would you make sure that all the lead oxide has been reduced ? ______________________________________________________________ ______________________________________________________________ [1 mark] (c) The table below shows the result of the experiment. [2 marks] (ii) Write a chemical equation for the reduction of lead oxide to lead.3.27 g 68. [Relative atomic mass : O. .67 g (i) Determine the empirical formula of lead oxide. Lead oxide is reduced using hydrogen gas in the experiment.87 g 65. Figure 2 The figure 2 shown above is used to determine the empirical formula of lead oxide. 207] (a) State two precautions that must be taken when carrying out this experiment. 16. Figure 3 shows the set-up of apparatus for an experiment to determine the empirical formula of magnesium oxide.0 g 26. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ [2 marks] 4.0 g (a) What is meant by empirical formula ? ______________________________________________________________ ______________________________________________________________ [1 mark] (b) Based on the above results. Figure 3 Result : Mass of crucible + lid Mass of crucible + lid + magnesium ribbon Mass of crucible + lid + magnesium oxide 24.______________________________________________________________ [1 mark] (d) Write an equation for the burning of excess hydrogen gas at the end of the heating tube.4 g 28. ______________________________________________________________ [1 mark] (e) Can the empirical formula of magnesium oxide be determined using the same arrangement of figure 2 as above ? Explain your answer. . [Relative Atomic Mass : O.(i) calculate the mass of magnesium and the mass of oxygen that have reacted. The apparatus provided are combustion tube. cork. 16. [2 marks] . Bunsen burner. Mg. (i) Draw a labelled diagram of the set-up of the apparatus for the experiment. [1 mark] (iv) write the chemical equation for the reaction in the experiment ______________________________________________________________ [1 mark] (c) Why was the crucible lid opened once in a while during the experiment ? ______________________________________________________________ ______________________________________________________________ [1 mark] (d) Metal X is places below hydrogen in the reactivity series. 24] [1 mark] (iii) determine the empirical formula of magnesium oxide. and porcelain dish. You are required to carry out an experiment to determine the empirical formula of the oxide of metal X. [1 mark] (ii) calculate the mole ratio of magnesium atoms to oxygen to atoms. glass tube. ______________________________________________________________ . Figure 4 shows part of the Periodic Table of the Elements. answer the following questions. X and Y according to the increase in size of the atoms. X and Y do not represent the actual symbol of the elements. R. ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ ______________________________________________________________ [3 marks] 5. T. T. Figure 4 (a) Using the letters in the Periodic Table of the Elements in Figure 4. (i) Choose an element that is a halogen. ___________________________________________________________ [1 mark] (ii) Which element is monoatomic ? ___________________________________________________________ [1 mark] (iii) Which elements forms an amphoteric oxide ? ___________________________________________________________ [1 mark] (b) Arrange Q. R. ______________________________________________________________ [1 mark] (c) Write the electron arrangement for an atom of element Q ______________________________________________________________ [1 mark] (d) Write the formula for the ion formed from an atom of element Y. Q.(ii) Describle the steps that should be taken to ensure that all the air in the combustion tube has been expelled. TOH solution is formed and hydrogen gas is released. . State one observation when red litmus paper is put into the solution. ______________________________________________________________ [1 mark] 3. Figure 2 shows part of the Periodic Table of Elements.[1 mark] (e) Why are elements Q and R placed in the same period ? ______________________________________________________________ [1 mark] (f) When a small piece of element T is put into water. ______________________________________________________________ [1 mark] (g) State the common name of the elements between group 2 and group 13. ________________________________________________________________ [1 mark] (c) Write the electron arrangement for the Mg and Al atoms. ______________________________________________________________ [1 mark] 4 Helium Gas light not reactive colourless Hydrogen Gas light flammable colourless . answer the following questions (a) What is the element represented by the symbol Fe ? ________________________________________________________________ [1 mark] (b) In Figure 2.Figure 2 Based on Figure 2. Mg : ___________________ Al : ______________________ [2 mark] (d) (i) Write the chemical equation for the reaction between Magnesium and oxygen gas. mark ‘X’ in the boxes for all the transition elements. ________________________________________________________________ [1 mark] (g) State one element that are same group as element Helium. ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ [2 marks] (f) What is the proton number of element O?.(e) Based on the above informations. which gas is more suitable to be used in meteorological ballons ? Give one reason. ________________________________________________________________ [1 marks] (h) State the elements that are: (i) Metal __________________________________________________ (ii) Non metal __________________________________________________ [2 marks] 5 Section B [20 marks] Answer any one question . O=16.00 g of element X. The relative atomic mass of four elements W. [2 amrks] (ii) 4. X. explain what is meant by the terms proton number. [Avogadro constant = 6x10 23 mol-1]. [7 marks] (c) (i) The chemical equation below shows the reaction between calcium carbonate and hydrochloric acid. 35. [9 marks] (b) Using 16 8 O and 17 8 O as example. what is the mass of 3. [4 marks] 8. answer the following question. forces of attraction between the particles. Ca=40 and the molar volume of any gas is 24 dm3 mol-1 at room temperature and pressure. Based on the above information. 7 (a) Compare the three physical states of matter in terms of particle arrangements.0 x 10 23 molecules of Y ? [2 marks] (c) Calculate the number of atoms in (i) 4. [2 marks] (h) What is the similarity between 40g of element X and 32g of element Z ? [ 2marks] .20 g of element Y [2 marks] [2 marks] [2 marks] (d) If the molecule of element Z is also diatomic. nucleon number and isotopes. (iii) 14. 40.5 and 16 respectively. (a) What is meant by the relative atomic mass of an elements ? [2 marks] (b) If the molecule of element Y is diatomic.60 g of element W. Elements W and X are metals whereas elements Y and Z are nonmetals. CaCO3 + 2HCl → CaCl2 + CO2 + H2O Given that the relative atomic mass of C=12.55 g of element Y. (ii) 8. calculate the number of molecules in (i) 3. Y and Z are 23. kinetic energy of the particles and compressibility.0 g od element Z.The time suggested to answer this section is 30 minutes. determine the empirical formula of the compaund formed. .2 g.20 g. [2 marks] (ii) 0.1 mole of the compound formed from W and Z has a mass of 6. [2 marks] Section C [20 marks] Answer any one question The time suggested to answer this section is 30 minutes. (i) 0.(g) For each of the following.1 mole of the compound formed from X and Z has a mass of 7. [5 marks] (c) Using chlorine. (a) With a suitable example. (a) Explain why the reactivity of Group 17 elements descrease down the group. explain how to carry out an experiment to determine the reactions of halogens with iron wool. [12 marks] 10. State the precautions that should be taken during experiment and write the observation and balance chemical equations. explain the following terms : (i) Relative molecular mass (ii) One mole of a subtance (iii) Molar mass (iv) Molecular formula [8 marks] (b) Group 1 elements are known as the alkali metals. explain why the electro-negativity of the elements increase across a period from left to right. State the precautions that should be taken during experiment and write the observation and balance chemical equations. sodium and potassium as example. bromine and iodine. Using lithium.9. explain how to carry out an experiment to determine the reactions of alkali metal with oxygen. [10 marks] . [5 marks] (b) Using a suitable period in the Periodic Table as an example.