2022 KC Chem Prelims P1

Name: _____________________________ ( ) Class:______ This question paper consists of 11 printed pages. [Turn over CHIJ KATONG CONVENT PRELIMINARY EXAMINATIONS 2022 Secondary Four Express CHEMISTRY 6092/01 Duration: 1 hour Classes: 405 and 406 Additional Material: Optical Answer Sheet. READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples, paper clips, highlighters, glue or correction fluid/ tape. Write your name, class and index number in the spaces provided at the top of this page and on the Optical Answer Sheet. There are forty questions on this paper. Answer all questions. For each question there are four possible answers, A, B, C and D. Choose the one you consider correct and record your choice in soft pencil on the separate Answer Sheet. Read the instructions on the Answer Sheet very carefully. Each correct answer will score one mark. A mark will not be deducted for a wrong answer. Any rough working should be done in the question booklet. A copy of the Periodic Table is printed on page 11. At the end of the examination, hand in: 1. Optical Answer Sheet; and 2. Question booklet separately. ���

CHIJ Katong Convent Prelim Exams 2022 Chemistry 6092/01 Sec 4E 2 [Turn over 1 Hydrogen chloride gas (Mr = 36.5) is released at P in the apparatus shown. The Universal Indicator paper turns red after 38 s. The experiment is repeated under the same conditions using sulfur dioxide (Mr = 64). Which shows the result for sulfur dioxide? Universal Indicator turns time for Universal Indicator to change colour/ s A blue 26 B blue 51 C red 26 D red 51 2 Substance M melts at –7.0 °C and is a brown liquid at room temperature. At which temperature(s) will pure M boil? A –77.0 °C B –7.0 °C to 7.0 °C C 48.0 °C to 65.0 °C D 59.0 °C 3 A student is asked to measure the time taken for 0.4 g of magnesium carbonate to react completely with 20.0 cm3 of dilute hydrochloric acid. Which pieces of apparatus does the student need? A electronic balance, burette, stopwatch B electronic balance, pipette, stopwatch C electronic balance, stopwatch, thermometer D stopwatch, pipette, thermometer 4 Rf values are used to identify unknown substances using paper chromatography. Which statements about Rf values are correct? 1 Rf values are always less than 1.0. 2 Rf value = distance travelled by solvent ÷ distance travelled by unknown substance. 3 The higher the Rf value, the further the unknown substance travels. 4 Rf values are not affected by the solubility of the unknown substance. A 1 and 2 only B 1 and 3 only C 2 and 3 only D 3 and 4 only Universal Indicator paper ���

CHIJ Katong Convent Prelim Exams 2022 Chemistry 6092/01 Sec 4E 3 [Turn over 5 Which physical property is used to separate the nitrogen and oxygen from air? A boiling point B density C electrical conductivity D molecular mass 6 Which statement about P, Q and R is correct? A P contains two compounds and R contains a mixture. B P contains two elements and Q contains a mixture. C P contains two elements and Q contains one compound. D Q contains two compounds and R contains a mixture. 7 The structure of an atom is shown. Which element is the atom an isotope of? A nitrogen B oxygen C phosphorus D titanium 8 Which row describes the structure of the positive ion in sodium chloride? protons electrons neutrons A 11 11 12 B 11 10 12 C 17 17 18 D 17 18 18 P Q R ���

CHIJ Katong Convent Prelim Exams 2022 Chemistry 6092/01 Sec 4E 4 [Turn over 9 Which row describes what happens to the electrons when lithium and nitrogen atoms form ions? lithium atoms nitrogen atoms A each lithium atom loses one electron to form a Li+ ion each nitrogen atom gains three electrons to form a N3– ion B each lithium atom loses one electron to form a Li– ion each nitrogen atom loses three electrons to form a N3+ ion C each lithium atom gains one electron to form a Li+ ion each nitrogen atom gains five electrons to form a N5– ion D each lithium atom gains one electron to form a Li– ion each nitrogen atom loses five electrons to form a N5+ ion 10 Which statement about metals is correct? A Layers of positive ions can slide over one another making metals malleable. B Metallic bonding consists of a lattice of negative ions in a sea of delocalised electrons. C Metallic bonding consists of a lattice of positive ions in a sea of delocalised negative ions. D Metals conduct electricity because positive ions are free to move. 11 Which statement is correct about the structures of both diamond and silicon(IV) oxide? A Molecules of both diamond and silicon(IV) oxide are held together by weak intermolecular forces of attraction. B The carbon in diamond and the silicon in silicon(IV) oxide each form four covalent bonds. C They both contain atoms arranged in planes held together by weak intermolecular forces of attraction. D They both contain ions that are free to move. 12 What is the total number of electrons in one molecule of ammonia, NH3? A 6 B 8 C 10 D 11 13 Four fertilisers are each supplied in 100 kg bags. Which fertiliser supplies the greatest mass of nitrogen per 100 kg bag? A ammonium nitrate, NH4NO3 B ammonium phosphate, (NH4)3PO4 C ammonium sulfate, (NH4)2SO4 D urea, CO(NH2)2 14 1 g of calcium carbonate is added to 50.0 cm3 of 0.050 mol / dm3 hydrochloric acid. The reaction is as shown. CaCO3 + 2HCl → CaCl2 + H2O + CO2 Which volume of carbon dioxide is produced in this reaction? A 30 cm3 B 60 cm3 C 120 cm3 D 240 cm3 ���

CHIJ Katong Convent Prelim Exams 2022 Chemistry 6092/01 Sec 4E 5 [Turn over 15 A tablet contains 0.080 g of ascorbic acid (Mr = 176). What is the concentration of ascorbic acid when one tablet is dissolved in 200 cm3 of water? A 0.0000909 mol / dm3 B 0.000455 mol / dm3 C 0.00227 mol / dm3 D 0.0909 mol / dm3 16 Which statement about amphoteric oxides is correct? A They are made by combining an acidic oxide with a basic oxide. B They react with water to give a solution of pH 7. C They react with both acids and bases. D They do not react with acids or bases. 17 Ethanoic acid is a weak acid. Hydrochloric acid is a strong acid. 1 Ethanoic acid molecules are partially dissociated into ions. 2 1.0 mol / dm3 ethanoic acid has a higher pH than 1.0 mol / dm3 hydrochloric acid. 3 Ethanoic acid is always more dilute than hydrochloric acid. 4 Ethanoic acid does not produce hydrogen ions. Which statements are correct? A 1 and 2 only B 1 and 3 only C 2 and 4 only D 3 and 4 only 18 When blue -green crystals of nickel(II) sulfate are heated, water is produced and a yellow solid remains. When water is added to the yellow solid, the blue-green colour returns. Which process describes these changes? A combustion B corrosion C neutralisation D reversible reaction 19 Lead(II) sulfate is prepared by mixing two substances, X and Y. When the reaction is complete, the mixture is filtered. Which row shows the best way to prepare pure lead(II) sulfate? substance X substance Y method after filtration A aqueous lead(II) nitrate aqueous sodium sulfate crystallise the filtrate B aqueous lead(II) nitrate aqueous sodium sulfate wash and dry the residue C solid lead(II) carbonate dilute sulfuric acid crystallise the filtrate D solid lead(II) carbonate dilute sulfuric acid wash and dry the residue ���

CHIJ Katong Convent P