Wynberg Boys High School

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1 Wynberg Boys High School Grade 10 Physical Sciences Test Topic: Matter and models 17 April Marks 50 Time 1 hour Set by Ty Moderated by Cl Instructions: 1 Answer ALL QUESTIONS on the answer sheet provided 2 Non-programmable calculators may be used 3 A periodic table can be found at the end of answer sheet Question 1 One word items Give one word / term for each of the following descriptions. Write only the word/term next to the question number ( ) on your ANSWER SHEET. 1.1 Atoms with the same atomic number, but different mass numbers. 1.2 The scientist who proposed that atoms have specific energy levels that the electrons can occupy. 1.3 The electrons in the outermost energy level. [3 x 1 = 3] Question 2 Multiple choice questions Four possible options are provided as answers to the following questions. Each question has only ONE correct answer. Choose the answer and write only the letter next to the questions number on your ANSWER SHEET. 2.1 The atomic number of an element is always the same as the number of: A nucleons B neutrons C electrons D protons 2.2 Alchemy is an ancient field of study that attempted to turn lead into gold. We now know that this can be achieved by A B C D removing 3 nucleons from the nucleus of a lead atom. adding 3 nucleons to the nucleus of a lead atom. removing 3 protons from the nucleus of a lead atom. adding 3 neutrons to the nucleus of a lead atom.

2 2.3 The correct name for Cu2O is: A B C D Copper (I) oxide Copper oxide (I) Copper (II) oxide Copper oxide (II) 2.4 The charge of an atom is: A positive B negative C neutral D none of these 2.5 Which of the following real atoms has twice as many neutrons as 12 6 C A 14 6 C B Na C Mg D O 2.6 If Rutherford had used neutrons instead of alpha particles in his scattering experiment, the neutrons would have: A B C D Not deflect because they have no charge deflected more often been attracted to the nucleus given the same results [6 x 2 marks = 12]

3 Question 3 Atomic structure Complete the following table on your ANSWER SHEET. Element Atomic number No. of protons No of neutrons No of electrons 24 Mg [7] Question 4 Isotopes Chlorine has two stable isotopes, namely chlorine-35 and chlorine-37. The naturally occurring percentages of each of these isotopes are 75,78% and 24,22% respectively. Use the above information to accurately calculate the relative atomic mass of chlorine. [3] Question 5 Models of the atoms From the following list, choose 3 scientists and explain their contribution to our understanding of the atom: Rutherford, Marie Curie, Democritus, Thomson (not the teacher, he s added NOTHING), Dalton, Chadwick [3] Question 6 Electron configuration and the periodic table 6.1 Draw the Lewis diagram for carbon dioxide. (2) 6.2 In a phosphorus atom, determine the number of: Core electrons (1) Valence electrons (1) 6.3 Give the electron configuration of sodium. (2) 6.4 Give the condensed/core electron configuration of sulphur. (2) 6.5 Explain why the atomic radius increases as you move down a group in the periodic table. (2) 6.6 Draw the Aufbau diagram for oxygen. (3) [13]

4 Question 7 Bonding 7.1 Calculate the relative molecular mass of methane (CH4). (2) 7.2 Determine whether the bonds in the following compounds are covalent, ionic or metallic: CO2 (1) MgF (1) 7.3 Using Lewis diagrams, show how a lithium atom and a chlorine atom bond together. (3) 7.4 Define the term electronegativity. (2) [9] Question 8 (Bonus question) How many atoms are in your body? You will need to make some estimates and approximations, which you should write down. [1] Total: 50

5 Wynberg Boys High School Grade 10 Physical Sciences Test Topic: Matter and Models 17 April Marks 50 Time 1 hour Set by Ty Answer sheet NAME: TEACHER: Question [1] 1.2 [1] Estimated Mark Actual Mark 1.3 [1] Question [6 x 2 marks = 12] Question 3 Element Atomic number No. of protons No of neutrons No of electrons 24 Mg

6 Question 4 Question 5 Question

7 Question BONUS QUESTION

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