ujian 2 KIMIA.

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Berikut adalah markah bagi ujian 2 KIMIA. 

KURSUS :KIMIA DAS 12203
NO.	MATRIC NO.	(%)
1	AA120336	81.3	A
2	AA110348	0.0	E
3	AA120620	77.5	A-
4	AA120327	72.5	B+
5	AA120066	66.3	B
6	AA121041	18.8	E
7	AA121047	11.3	E
8	AA120297	23.8	E
9	AA120255	56.3	C+
10	AA121062	37.5	E
11	AA120107	35.0	E
12	AA121063	8.8	E
13	AA120802	67.5	B
14	AA121075	42.5	D
15	AA121077	15.0	E
16	AA120207	60.0	B-
17	AA121081	73.8	B+
18	AA120713	37.5	E
19	AA121086	20.0	E
20	AA120234	41.3	D
21	AA120483	85.0	A+
22	AA120474	33.8	E
23	AA120714	28.8	E
24	AA121089	10.0	E
25	AA120895	45.0	C-
26	AA120165	35.0	E
27	AA121095	52.5	C
28	AA121096	20.0	E
29	AA121101	41.3	D
30	AA121104	7.5	E
31	AA121114	25.0	E
32	AA120334	7.5	E
33	AA121123	66.3	B
34	AA121126	22.5	E
35	AA120073	37.5	E
36	AA121128	33.8	E
37	AA120481	42.5	D
38	AA121130	42.5	D
39	AA121136	17.5	E
40	AA120930	63.8	B-
41	AA121140	21.3	E
42	AA120593	72.5	B+
43	AA121146	0.0	E
44	AA120433	26.3	E
45	AA121163	67.5	B
46	AA120119	35.0	E
47	AA121015	51.3	C
48	AA121179	53.8	C
49	AA120552	0.0	E
	KURSUS :KIMIA DAS 12102
NO.	MATRIC NO.	(%)
1	BA10109	6.3	E
2	AA10670	13.8	E
3	BA10063	0.0	E
4	BA10054	0.0	E
5	BA10219	52.5	C
6	BA10088	16.3	E
7	BA10029	18.8	E
8	BA10259	20.0	E
9	AA111309	66.3	B
KURSUS :KIMIA DSK 1913
NO.	MATRIC NO.	(%)
1	AD09589	0.0	E
2	AF09221	35.0	E
3	AF09222	78.8	A-
KURSUS :KIMIA DSK 1912
NO.	MATRIC NO.	(%)
1	AE09238	3.8	E
2	AE09381	8.8	E
3	AE09237	2.5	E

tutorial 2 DAS12203

Tutorial 2

1.	(a)	At -15 °C, a natural gas storage tank has volume of 3.25 x 103 L. what is the volume at 31 °C? (3.83 x 103 L)
	(b)	A 50.0 L sample of gas is at 3.00 atm of pressure and a temperature of 298 K. What volume would the gas occupy at STP? (137.4 mL)
	(c)	Tennis balls are filled with nitrogen gas, N2 to increase their “bounce”. Find the pressure inside the tennis balls if it contains 0.33 g of N2 gas at 24 °C and given the volume of the ball is 144 mL. (RAM: N = , R = ) (2 atm)
2.	(a)	For the reaction : NO(g)  +  O2(g)   à   N2O3(g) (i)                 Balance the equation (2NO(g) + 1/2O2(g)  à  N2O3(g)) (ii)  Express the rate in terms of the change in concentration with time for each substance. (iii)             How fast is [O2] decreasing when [NO] is decreasing at a rate of 1.60 x 10-4 mol/L.s? (4 x 10-5 mol/L.s)
	(b)	For the reaction: CF4(g) + H2(g) à CHF3(g) + HF(g), the following data were obtained at 1100 K Exp [CF4(g)] mol/L [H2(g)] (mol/L) Initial rate (mol/L.s) 1 2 3 4 0.1 0.15 0.20 0.20 0.10 0.10 0.20 0.30 45.0 67.5 180 270 (i)                 Write the rate law of the reaction. (x = 1, y = 1) (ii)               Calculate the average value of the rate constant. (4500)
3.	(a)	A layer of copper welded to the bottom of a skillet weighs 125 g. how much heat is needed to raise the temperature of the copper layer from 25 °C to 300 °C? (sCu = 0.387 J/g.C) (13.303 kJ)
	(b)	When 1 mol of KBr(s) decomposes to its elements, 90.29 kJ of heat is absorbed. (i)    Write the balance thermochemical equation for this reaction. (2K(s) + Br2(l)  à  2KBr(s)    ∆H = -90.29 X 2 kJ) (ii)  How much heat is released when 13.5 kg of KBr forms from its elements (reverse reaction from (i)) (RAM: K = , Br = ) (1.02 X 104 kJ )
4.	(a)	Draw Lewis structure for the following molecules, including all formal charges. Also include resonance structure where appropriate. (i)                 CO (ii)               CO2 (iii)             CH4 (iv)             MgCl2 (v)               BeI2
5.	(a)	A 4.50 g gold nugget (specific heat, 0.129 J/g °C) absorbed 276 J of heat. Calculate the final temperature of the gold nugget if the initial T was 25.0 °C (500.5 °C)
	(b)	Given the following thermochemical equation: 3C(s) +2Fe2O3(s) à 4Fe(s) + 3CO2(g)  ∆H = 466 kJ (i)                 Calculate ∆H for the reaction of 2 moles of C. (310.7 kJ0 (ii)               How much heat is required to produce 1000 kg of Fe? (RAM: C= , O=, Fe=,) (2.1 x 106 kJ)
	(c)	Calculate ∆Hf° FeS from the following thermochemical equation: 4FeS(s) + 7O2(g) à 2Fe2O3(s) + 4SO2(g) ∆H = -2435.6 kJ Given: ∆Hf° Fe2O3 = -824.2 kJ/m;, ∆Hf°SO2 = -296.8 kJ/mol (-100 kJ/mol)

tutorial 1 DAS12203

Tutorial 1

1.	(a)	Calculate the volume that 0.80 g methane, CH4 occupies at 52 °C and 100 kPa. (RAM: H, C, R)
	(b)	Zinc metal react with hydrochloric acid to produce hydrogen gas, H2. Zn (s)  +  HCl (aq)   à   ZnCl2 (aq)   +   H2 (g) The volume of H2 collected over water at 23 °C is 260 ml and the total pressure is 740 mmHg. (Water vapour pressure at 23 °C is 21.1 mmHg). (i)                 What is the partial pressure of H2? (ii)               How many milligrams of H2 were collected? (RAM: H, Cl, Zn, R)
2.	(a)	The first step in industrial recovery of zinc from th zinc sulphide ore is roasting: 2ZnS (s)  +  3O2 (g)   à  2ZnO (s)   +   2SO2 (g)   ∆H = -879 kJ/mol (i)                 Skecth an enthalpy diagram of the process. (ii)               Calculate the heat evolved (in kJ) per gram of ZnS roasted. (RAM: Zn, S)
3.	(a)	Consider the reaction  A à  B. The rate of the reaction is 1.6x10-2 Ms-1 when the concentration of A is 0.35 M. Calculate the rate constant, k if the reaction is (i)                 First order in A (ii)               Second order in A
		(i)
	(b)	(ii)     Define the half-life of a reaction. (iii)   Write the equation relating the half life of a first order of reaction to the rate constant, k. (iv)   Determine the half life of a compound if 75 % of a given sample of the compound decomposes in 60 min. Assume first order kinetics.
	(c)	The rate constant for a second order reaction 2NO2 (g)  à  2NO (g)  +  O2 (g) is 0.54 M-1s-1 at 300 °C. How long (in second) would it take for the concentration of NO2 to decrease from 0.562 M to 0.128 M.
4	(a)	Adenosine triphosphate (ATP) contain 10 carbon, 11 hydrogen, 13 oxygen, 5 nitrogen and 3 phosphorous atoms per molecule. (i)                 Write the molecular formula of ATP. (ii)               What is the number of ATP molecules in 10.0 g of ATP? (RAM: H, C, N, O, P, NA)
5.	(a)	Draw the lewis structure of ammonium ion, NH4+ and determine the formal chargefor each atom in the ion. (Atomic no., Z: N, H)
	(b)	(i) Which of the following are exceptions to the Lewis octet rule? BeF2 or SO3 (ii) Use forma charge to prove that the structure you choose in (i) is stable (Atomic no.,Z: Be=, O=, F=, S=,)
	(c)	Draw Lewis structure and the resonance forms of NO2F (N is cetral atom). (atomic no., Z: N=, O=, F=,)
6.	(a)	What is the molar mass of a gas that has density of 575 g/L at STP? (R =    )
	(b)	Boron hydride, B4H10­ reacts with oxygen to produce B2O3 and H2O 2B4H10 (s)   +   11O2(g)   à   4B2O3 (s)   +   10H2O (g) If 0.05 g B4H10 reacts with excess O2 (i)                 Write the stoichiometric relationship between B4H10­ and H2O (ii)               Find the number moles of B4H10­ and H2O (iii)             What is the pressure of the gaseous H2O in 425 L flask at 30 °C? (RAM: H, B, O, R = )
7.	(a)	A 100.0 g copper sample at 100 °C is added to 50.0 g of water at 26.5 °C. Determine the final temperature of the copper – water mixture. (SCu = 0.385 J.g-1.°C-1, Swater = 4.184 J.g-1°C-1)
	(b)	Calculate ∆H for the reaction N2H4 (l)  +  2H2O (l)  à  N2 (g)  +  4H2O (l) Given the following set of reaction N2H4 (l)  +  O2  à  N2 (g)  +  2H2O (l)                  ∆H = -622.2kJ H2 (g)  +  1/2O2 (g)  à  H2O (l)                             ∆H = -285.8 kJ H2 (g)  +  O2 (g)  à  H2O2 (l)                                 ∆H = -187.8 kJ