C2 H2 Chemistry Block Test 1 2012_RevisionQuestions
-
Upload
michael-calderone-chee -
Category
Documents
-
view
853 -
download
12
Transcript of C2 H2 Chemistry Block Test 1 2012_RevisionQuestions
![Page 1: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/1.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 1
Name: ( ) CT Group: ________
C2 H2 Chemistry Block Test 1 2012
Overall Paper Format
Paper Type No. of questions No. of marks Duration
1 MCQ 20 20 30 min
2 Section
A:Structured
3 or 4
(includes
Planning)
40 60 min
Section B:
Free Response
1 20 30 min
Total 80
Paper 1 administered first followed by Paper 2 with a 15 min interval. 5 min break after Paper 2 Section A to hand in Section A and start
Section B. Topics Tested 1) Reaction Kinetics
2) Acid-Base Equilibrium
3) Introduction to Organic Cmpds
4) Alkanes
5) Alkenes
6) Arenes
7) Halogen Derivatives
8) Alcohols & Phenols
9) Carboxylic Acids & Derivatives
10) Aldehydes & Ketones ( MCQ only)
11) Planning
Marks:
Q1 /13 Q5 /20
Q2 /7 Q6 /20
Q3 /4 Extension 6b /3
Q4 /8 TOTAL /75
Note:
This paper does not test on alkanes and alkenes – you're expected to have already
studied them and be able to draw the mechanisms for any of the reactions.
![Page 2: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/2.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 2
1. [HCI 2009/2/2a,b,c] Glycolic acid CH2(OH)CO2H is an α-hydroxy acid (AHA)
used in various skin-care products.
a) 0.200 g of glycolic acid (Mr = 76.0) was dissolved in 20.0 cm3 water, and the
solution was titrated with 0.100 mol dm–3 aqueous NaOH. The following titration curve was obtained. (Ka of glycolic acid = 1.48 x 10–4 mol dm–3)
i) Calculate the volume of NaOH required to reach the equivalence point
in the titration.
ii) Calculate the pH of the solution at equivalence point.
![Page 3: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/3.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 3
iii) The table below shows the working range of some acid-base indicators.
Suggest an indicator which can be used in this titration and give a
reason for your choice.
[5]
b) Glycolic acid can undergo a series of reactions as shown below.
Step 1 Step 2
Multiple Steps Step 3
A
B
C
![Page 4: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/4.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 4
a) What reagents and conditions are required for the following steps?
i) Step 1:
ii) Step 2: ________________
iii) Step 3: ________________
b) Arrange the three compounds A, B, C in order of increasing ease of hydrolysis, giving your explanations clearly.
__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________. [6]
c) Compounds D and E below are also common α-hydroxy acids.
State the reagents and conditions you would use and the observations you would expect to make, in a simple chemical test, to distinguish glycolic acid from
i) Compound D:
ii) Compound E:
[2]
![Page 5: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/5.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 5
2a) Sulfuric acid, under different conditions, can behave as a dehydrating agent, a catalyst, an acid or an oxidizing agent. [7]
i) By means of equations, give one different reaction in each case where concentrated sulfuric acid behaves as a:
- Dehydrating agent
- Catalyst
ii) Using the reaction between concentrated sulfuric acid and sodium sodium bromide, write an equatino, including state symbols, to illustrate how concentrated sulfuric acid behaves as an:
- Acid
- Oxidizing Agent
b) Benzedrin is a stimulant and has the following structual formula:
Draw the structure of the organic products when benzedrin reacts with each of the following reagents:
a) Dilute nitric acid
![Page 6: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/6.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 6
b) Ethanoyl chloride
c) NaOH (aq), followed by CH3I and heat.
3) HCN gas is a highly poisonous gas that can cause permanent
damage to the central nervous system. The toxic level of HCN gas in the air is
about 0.001 mg dm-3.
a) Express the toxic level of HCN gas in the air in terms of mol dm-3. [1]
b) Describe the mechanism for the formation of cyanohydrins starting from propanal and HCN. [3]
4)
i) Account for the difference in the melting points of sodium chloride and silicon tetrachloride. [2]
ii) Explain briefly the difference in the pH values when MgCl2, AlCl3 and PCl5 are separately dissolved in water. Use equations to support your answer. [6]
![Page 7: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/7.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 7
5)
k
![Page 8: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/8.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 8
![Page 9: C2 H2 Chemistry Block Test 1 2012_RevisionQuestions](https://reader031.fdocuments.in/reader031/viewer/2022013121/5440cf35b1af9f5a118b45de/html5/thumbnails/9.jpg)
HWA CHONG INSTITUTION C2 Block Test 1 H2 Chemistry 9746 Revision Questions
Prepared by Chee Yuan Jun 9
6) [N2011/3/5]
Extension 6b) Outline the mechanism for the conversion of phenol to 4-nitrophenol. [3]