Section A Multiple Choice

Transcription

1 Section Multiple hoice 1. Two atoms have the same atomic number but different mass numbers. The atoms are two different elements have different numbers of electrons have different numbers of protons are isotopes of the same element 2. neutral atom contains 15 electrons. It would be found in group 5 of the periodic table It would be found in the 15 th period of the periodic table It would most likely form a 3 + ion. It would be found in period 2 of the periodic table. 3. Two subatomic particles are found in the nucleus of an atom. They are: protons and electrons protons and isotopes neutrons and electrons protons and neutrons. 4. ow many neutrons and electrons are present in an ion with a +2 charge, an atomic number of 18 and mass number of 38? 18 neutrons and 16 electrons 38 neutrons and 20 electrons 20 neutrons and 18 electrons 20 neutrons and 16 electrons 5. What is the maximum number of electrons in the second shell of an atom? n ion has 12 protons and 10 electrons. The ion is: F 2- Mg 2- F 2+ Mg 2+

2 7. Which one of the following species has the greatest number of neutrons in its nucleus? 56 Mn Ni o Fe bromide ion is composed of 36 electrons, 35 protons and 44 neutrons. The ion is represented by the symbol: 44 r r r r Which one or more of the following pairs of elements react(s) to form a compound containing covalent bonds? potassium and fluorine hydrogen and oxygen oxygen and calcium arbon and chlorine 10. Element X has an electronic configuration of 2,8,3. It is likely to form the compound: Xl 3 MgX XSO 4 X 2 (PO 4 ) n unknown element which forms ionic compounds with fluorine of the form XF 2 would come from: Group I (1) Group II (2) Group VI (6) Group VII (7)

3 12. n equation for the reaction when calcium metal and oxygen gas combine to form calcium oxide is stated incorrectly as: a (s) + O 2 (g) 2aO (s) This equation is not correct because: no charges have been shown on calcium and oxygen a is not the correct symbol for alcium metal The equation is not correctly balanced. ao is not the correct formula for calcium oxide 13. The electronic configurations of three elements are: Y = (2, 6) X = (2, 8, 2) Z = (2, 8, 5) Which two elements form covalent bonds with each other? X and Y X and Z Y and Z None of the above 14. Propane burns in air according to the equation: w + xo yo + z 3 8(g) 2(g) 2(g) 2O (g) The values of w, x, y and z needed (in order) to balance this equation are 1, 5, 3, 4. 1, 10, 3, 4. 2, 5, 6, 4. 1, 3, 3, Which of the following equations can be completed correctly by replacing X with 2 2 O? N 3(g) +2O 2(g) NO 3(l) + X. 2l (aq) +MgO (s) Mgl 2(aq) + X (g) +13O 2(g) 8O 2(g) + X. 2 SO 4(aq) +a(o) 2(aq) aso 4(s) + X. 16. Which of the following substances has the greatest mass? 2.5 mol of hydrogen gas, mol of zinc, Zn 11.56g of calcium chloride, al x atoms of oxygen

4 17. The mass of one mole of iron (III) sulfate, Fe 2 (SO 4 ) 3, is closest to 100g 200g 300g 400g 18. The percentage by mass of hydrogen in methane ( 4 ) is: 20% 25% 50% 75% 19. The most appropriate moulding process for the production of a plastic bottle is: injection moulding extrusion moulding blow moulding cold compression moulding 20. omponents in crude oil are separated according to differing: boiling points densities relative atomic masses heat conductivity 21. racking is a process where: light fractions are broken down into heavier fractions. heat is used to decompose crude oil. heat or a catalyst are used to increase the proportion of short chain molecules. heat or a catalyst are used to increase the proportion of long chain molecules. 22. In the following reaction: 4 + 2O 2 O O the combustion is complete. the equation is not balanced. methane and oxygen are the only products. 2 moles of water are produced for every 1 mole of oxygen consumed.

5 23. Look at the following organic structure and determine its correct name: 3 eptane 4 eptene 3 eptene 4 - eptyne 24. Which of the following is the monomer unit that forms the polymer section shown below: F F F F F F 25. Thermosetting plastics always: have no crosslinking between polymer chains. have strong crosslinking between polymer chains. remould very easily after gentle heating. contain unconnected chains that move past each other with gentle heating. 26. The speed of radio waves in air is closest to 100 m/s 300 km/s km/s km/s 27. Which of the following is not an example of electromagnetic radiation? Light Microwaves Sound Ultraviolet radiation

6 28. The series of waves shown below was produced in 20 seconds. hoose the correct answer: The amplitude of the wave is 10mm. The wavelength of the wave is 30mm. The wave has a frequency of 20z. The wavelength of the wave is 10mm. 29. What is the effective resistance of the following circuit? 8Ω 8Ω 2Ω 4Ω 8Ω 16Ω 30. What is the effective resistance of the following circuit? 8Ω 10Ω 10Ω 28Ω 18Ω 13Ω 9Ω

7 Section Short nswer Question 1: sodium atom has 11 protons and 12 neutrons. a) What is its atomic number? b) ow many electrons does a sodium atom have? c) What is the mass number of a sodium atom? Question 2: Write the chemical symbol for each of these elements: a) Silicon b) Sodium c) Sulphur d) Samarium e) Tin f) Silver g) Selenium h) Strontium Question 3: The elements magnesium and calcium behave similarly in chemical reactions. raw electron configuration diagrams of the atoms of both elements and explain how these electron arrangements may give some clue to the similarity in chemical behaviour of the two elements. (2 marks) Magnesium alcium Question 4: Name two elements which have similar chemical properties to: a) Fluorine b) Sodium (2 marks)

8 Question 5: Use electron shell diagrams to determine the formula of the ionic compound formed between sodium (atomic number 11) and oxygen (atomic number 8) Question 6: Using the electrovalency table provided, write the correct formula for each of the following: alcium carbonate Sodium sulfate Magnesium nitrate luminium oxide Potassium permanganate Tin Oxide Question 7: alance the following equations: a) KlO 3 K l + O 2 b) ZnO 3 + NO 3 Zn(NO 3 ) 2 + O O c) Fe 2 O 3 + O Fe + O 2 e) 2 + O 2 2 O f) Mg + l Mgl (5 marks) Question 8: What feature of the atoms of the noble gases causes them to be so stable and unreactive? ( 2 marks)

9 Question 9: Explain why carbon usually forms four covalent bonds. Question 10: Write a balanced chemical equation, showing states, for each of the following: ( 1 mark) a) The heating of solid copper (II) carbonate produced solid copper (II) oxide and carbon dioxide gas. b) Iron (III) chloride solution reacts with sodium carbonate solution to form the precipitate iron (III) carbonate and sodium chloride solution. Question 11: ow many atoms of hydrogen are present in each of the following formulas? (a) 2 O 2 (b) (N 4 ) 2 PO 4 Question 12: What is the molar mass of each of the following substances? (a) 2 O 2 (b) (N 4 ) 2 PO 4 Question 13: Using a periodic table, answer the following questions. a) What is the mass (in grams) of four moles of oxygen atoms? (5 marks) (2 marks) (2 marks) b) What is the mass (in grams) of one mole of sulfur atoms? c) What is the mass (in grams) of two moles of hydrogen atoms? d) What is the relative molecular mass of sulphuric acid ( 2 SO 4 )? e) If I have 147 grams of sulphuric cid ( 2 SO 4 ), how many moles do I have? ( = 6marks)

10 Question 14: The equation for the production of glucose by photosynthesis is: 6O O 6 12 O 6 + 6O 2 alculate the mass of carbon dioxide required to produce 36 grams of glucose. Question 15: omplete the following table: Name of organic molecule Structural diagram O 4 - nonyne 3 - hexanol 2 - octene (5 marks)

11 Questions 16: Refer to the following diagram: mplitude 2 m 1 m Time (s) m 2 m a) What is the amplitude of the wave? b) What is the period of the wave? c) What is the frequency of the wave? d) If the above wave has a wavelength of 12m, what is the speed at which the wave travels? e) raw on the axes above a wave with twice the frequency and half the amplitude. ( = 6 marks)

12 Question 17: What is the effective resistance for each of the following circuits? 4Ω 12Ω 13Ω 11Ω 5Ω 20Ω 20Ω 10Ω 10Ω 10Ω R R R R Question 18: What is the effective resistance for each of the following circuits? (2 marks) 4Ω 5Ω 3Ω 3Ω 6Ω 6Ω 8Ω 8Ω 2Ω 2Ω 5Ω 5Ω 16Ω 16Ω R R R R (4 marks) Question 19: Using an unlimited supply of 2Ω and 10Ω resistors, draw a circuit that has an effective resistance of: (a) 12Ω (b) 11Ω (c) 15Ω (d) 8.33Ω (4 marks)

13 Question 20. alculate the resistance for the circuit above, when the voltage is 15V and the current is 2. Resistor Voltage 3 2 Resistor urrent Question 28: The graph above has the voltage current characteristics for resistor and resistor. Which resistor has the highest resistance, Resistor or Resistor? Justify your answer with a calculation.