CHEM1902 Example Multiple Choice Questions

Transcription

1 M902 xample Multiple hoice Questions The following multiple choice questions are provided to illustrate the type of questions used in this section of the paper and to provide you with extra practice. It is not a sample quiz. The questions in the paper will be in the style of these questions but may well cover different topics. In the exam, the answer should be indicated by clearly circling the letter next to the choice you make and by filling in the corresponding box on the computer-marked sheet provided. The marks for each correct answer are given beside each question. Instructions for use of the computer sheet. raw a thick line through the centre and crossing both edges of each box selected, as in this example. Use a dark lead pencil so that you can use an eraser if you make an error. rrors made in ink cannot be corrected you will need to ask the examination supervisor for another sheet. oxes with faint or incomplete lines or not completed in the prescribed manner may not be read. e sure to complete the SI and name sections of the sheet. Your answer as recorded on the sheet will be used in the event of any ambiguity. There is only one correct choice for each question. Negative marks will not be awarded for any question.

2 M902 November 20 xample Multiple hoice Questions In answering questions - 5, choose from compounds -. O O O O 3 3 N O 3 3. Which one of the compounds - is a primary alcohol? 2. Which one of the compounds - will react with NaO in an acid-base reaction? 3. Which one of the compounds - will react with l to form a quaternary ammonium salt? 4. Which one of the compounds - will react with dimethylamine, ( 3 ) 2 N, to give an amide? 5. Which one of the compounds - will form a carboxylic acid upon treatment with acidified Na 2 r 2 O 7 solution? 6. Which one of the following is the most stable carbocation? N For questions 7 -, choose from - the term that best describes the relationship between each of the following pairs of compounds.. onformational Isomers. onstitutional Isomers. nantiomers. iastereomers. Identical ompounds 7. r r

3 M902 November 20 xample Multiple hoice Questions 8. l 3 3 l r 3 3 r 9. r r O O In answering questions 2-7, choose from the molecules -. O O O l 2. Which one of compounds - can react with l in an electrophilic addition reaction? 3. Which one of compounds - will be formed upon the oxidation of 2-butanol? 4. Which one of compounds - will react with Na 4 followed by aqueous acid to give a primary alcohol? 5. Which one of compounds - undergoes an elimination reaction on treatment with hot alcoholic potassium hydroxide solution?

4 M902 November 20 xample Multiple hoice Questions 6. Which one of compounds - is an example of a conjugated molecule? 7. Which one of compounds - will form 2-methyl-2-bromobutane upon treatment with r? 8. Rank the following series of atoms in order of INRSING electronegativity. N O F P s N < O < F < P < s F < O < N < P < s s < P < N < O < F s < P < N < F < O F < N < O < s < P In answering questions 9-20, consider the following titration curve. 2 0 p mount of solution added (ml) 9. Which one of the following combinations does the titration curve represent? ddition of a strong base to a weak acid ddition of a weak base to a strong acid ddition of a weak acid to a strong base ddition of a strong acid to a strong base ddition of a strong acid to a weak base

5 M902 November 20 xample Multiple hoice Questions 20. What is the value of the pk a that can be obtained from this titration curve? Which intermolecular forces are present in phenol, 6 5 O(s)? London dispersion only ipole-dipole only ydrogen-bonding only London dispersion and dipole-dipole London dispersion, dipole-dipole and hydrogen bonding 22. catalyst speeds up a chemical reaction by changing the stoichiometry. increasing the activation energy. providing an alternative reaction mechanism of lower activation energy. shifting the equilibrium towards the side of the product(s). increasing the reaction enthalpy. 23. Which of the following gases can be liquefied at 25? Gas ritical point 3 l 44, 66 atm SO 2 58, 78 atm 4 82, 46 atm SO 2 only 4 only 3 l and SO 2 all of them none of them

6 M902 November 20 xample Multiple hoice Questions 24. solid has a very high melting point, is very hard, and its liquid is nonconducting. The compound is a molecular solid. a metallic solid. a covalent network solid. an ionic solid. an amorphous solid. 25. When one mole of ice melts to liquid at 0, the entropy of the system decreases. the entropy of the system remains the same. the entropy of the system increases. the order of the system increases. None of the above 26. The entropy of a chemical system will usually increase when a molecule is broken down into two or more smaller fragments. a reaction occurs that results in an increase in the moles of gas. a solid changes to a liquid. a liquid changes into a gas. ll of the above 27. rrange the common unit cells of metals from the least dense packing to the most dense packing. body-centred cubic < face-centred cubic < simple cubic body-centred cubic < simple cubic < face-centred cubic face-centred cubic < simple cubic < body-centred cubic simple cubic < body-centred cubic < face-centred cubic simple cubic < face-centred cubic < body-centred cubic 28. ow many atoms are there in the face-centred cubic unit cell of iron? # atoms = (8) = 8 # atoms = + (8) = 2 8 # atoms = (6) = 3 2 # atoms = (6) + (8) = # atoms = + (6) + (8) = 5 2 8

7 M902 November 20 xample Multiple hoice Questions 29. The normal boiling point of a liquid is the only temperature at which there can be equilibrium between the liquid and gas states. the temperature above which the substance cannot exist as a liquid regardless of the pressure. the temperature at which the entropy of the liquid is equal to zero. the temperature at which the vapour pressure of the liquid equals the ambient atmospheric pressure. the temperature at which the vapour pressure of the liquid equals atm. 30. What is the geometry of the [r(o 2 ) 6 ] 3+ ion? tetrahedral trigonal bipyramidal square planar octahedral linear 3. What is the ground state electronic configuration of Fe 3+? [r] 3s 2 3p 6 [r] 4s 2 3d 4 [r] 4s 2 3d 3 [r] 4s 0 3d 8 4p 2 [r] 4s 0 3d Which of the following species exist as isomers? [o(n 3 ) 6 ] 3+, [Ptl 2 (N 3 ) 2 ], [o(o 2 ) 6 ]l 3, [o(o 2 ) 6 ] 2+, [di 4 ] 2 [Ptl 2 (N 3 ) 2 ] and [o(o 2 ) 6 ]l 3 [Ptl 2 (N 3 ) 2 ] only [di 4 ] 2 only [o(n 3 ) 6 ] 3+ and [o(o 2 ) 6 ] 2+ [o(o 2 ) 6 ]l 3 and [o(o 2 ) 6 ] 2+

8 M902 November 20 xample Multiple hoice Questions nswers Question nswer Question nswer Question nswer Question 3 32 nswer