i need jupeb past questions?

aderojurichard9

10 months ago

CHM 003
6. (a). Write an equation for the synthesis of hydrogen gas by the reaction of methane with
steam. [1 mark]
(b). Compare the physical and chemical properties of the hydrides of; Na, C, N and S
[3 marks]
(c). Explain using equation why rain falling in unpolluted air is acidic with a pH of about
5.6.
[2 marks]
(d). Acid rain has a pH value less than 5.6. Explain using equation how the burning of
coal can contribute to acid rain formation. [2 marks]
(e). What are the consequences of global warming on the environment? [2 marks]
CHM 004
7. An organic compound X contains 40% carbon, 53.3% oxygen and 6.7% hydrogen.
The vapor density of X is 30. The organic compound reacted with sodium hydrogen
trioxocarbonate (IV) and a colorless gas was given off which turned lime water milky.
On boiling under reflux, the mixture of X and ethanol, a sweet smelling liquid Y was
formed.
(a). Determine the (i) empirical and (ii) molecular formula of X. [4 marks]
(b). What is the name of the colourless gas given off? [1 mark]
(c). Give the formula of the functional group present in X. [1 mark]
(d). Deduce the structure of the compound X [1 mark]
(e). Name the reaction which took place between X and ethanol, and write an equation for
the reaction between X and ethanol. [3 marks]
CHM 002
8. (a). State three (3) major factors, which affect the discharge of ions at the electrodes
during electrolysis. [3 marks]
(b). Explain why a tin-plated iron container corrodes faster than a galvanized iron
container with reference to the electrochemical series. [2 marks]
(c). 528g of a trivalent metal is deposited when a current of 1.56A is passed through a
solution of its salt for 1hour; calculate the relative atomic mass of the metal. Hence
identify the metal. (1F = 96500C) [2 marks]
(d). State any three (3) common applications of electrolysis. [3 marESSAY QUESTIONS\; Answer FOUR Questions in all; One from each
Course
CHM 002
1. (a) Explain the condition of chemical equilibrium using the hypothetical equilibrium
equation;
[3 marks]
(b) Write the equilibrium constant, Kc expressions for the following reactions
[1 mark]
[1 mark]
[1 mark]
(c) A mixture of 0.003 mol of H2 and 0.002 mole of I2 were reacted to attain equilibrium
in a 2- L container at 400 o
C. Analysis of the equilibrium mixtures shows that the
concentration of HI is 0.0022 M. Calculate Kc for the reaction at 400 o
C.
[4 marks]
CHM 004
2. Crude oil is the principal source of hydrocarbons. The following are examples of such
hydrocarbons.
(a). Give the structural formulae of the organic products in the following reactions.
(i) The reaction of ethane with bromine in the presence of U.V. light. [1 mark]
(ii) The reaction of HBr with butene. [1 mark]
(iii) The reaction of cyclohexene with hydrogen bromide. [1 mark]
(b). Write equations for the following reactions.
(i) The complete combustion of propane. [1 mark]
(ii) The action of steam on propene in the presence of a catalyst. [1 mark]
(iii) The reaction of cyclohexene with hydrogen in the presence of a catalyst. [1 mark]
(c). Write a structural formula for each of the following and indicate whether it is primary,
secondary or tertiary.
(i) 3 – pentanol (ii) 2,2 - dimethyl -1- propanol (iii) 1 - methyl cyclopentanol(iv) 2 -
methyl -2- propanol [4 marks]CHM 001
3. (a). Explain the following terms:
(i) Precision
(ii) Accuracy.
(4marks)
(b). The concentration of Nickel in Nigerian coin was determined with visible
spectrophotometer, and the following results (%) were obtained: 3.65, 4.11, 3.59, 7.51, 3.95,
3.87, 4.06, 1.48, 3.60, 3.76 and 3.99. if the true concentration (%) of nickel in coin as
determined by atomic absorption and inductively coupled plasma atomic emission
spectrophotometer was 3.92.
Use the above data to determine:
(i) Absolute error
(ii) Percentage relative error
(iii) Average error (6 marks)
CHM 003
4. (a).Name the strongest type of intermolecular force between hydrogen fluoride
molecules and draw a diagram to illustrate how two molecules of HF are attracted
to each other.
In your diagram show all lone pairs of electrons and any partial charges. Explain
the origin of these charges.
Suggest why this strong intermolecular force is not present between HI
molecules. [3 marks]
(b). Crystals of sodium chloride and of diamond both have giant structures. Their
melting points are 1074 K and 3827 K, respectively. State the type of structure
present in each case and explain why the melting point of diamond is so high.
[3 marks]
(c). Write a Lewis structure and identify the octet-rule exception for (i) SClF5 (ii)
BFCl2 [4 marks]
CHM 002
5. (a). State Gay-Lussac’s law [2 marks]
(b). State Afbau’s principle and Hund’s rule of maximum multiplicity. [2 marks]
(c). what do you understand by a Bronsted acid? [1 mark]
(d). briefly explain the term “Inert Pair Effect” [2 marks].
(e). Compare and contrast the following properties of the transition elements with that of S
and P- block elements. (i) Colour (ii) Atomic / ionic radius (iii) oxidation states. [3 marks]
Uploa43. When azimuthal quantum number (l = 2), what set of orbitals is designated?
A. p
B. d
C. f
D. g
44. Sodium hydroxide is an Arrhenius base because it contains ________.
A. Na+
B. OH-
C. NaOH
D. Na
45. The standard state of an element or compound is determined at a pressure of and a
temperature of _______.
A. 760 mmHg, 0 o
C
B. 1 atm, 273 o
C
C. 760 mmHg, 0 K
D. 1 atm, 298 K
46. Which of the following is a state function?
A. enthalpy
B. work
C. heat
D. power
47. The method that cannot be used for removing permanent hardness of water is _______.
A. adding sodium carbonate
B. boiling
C. adding caustic soda
D. adding slaked lime
48. In which of the following characteristics does hydrogen resemble halogens?
A. Hydrogen is the lightest
B. Hydrogen forms ionic hydrides with alkali metals
C. Hydrogen atom contains one electron each
D. Hydrogen has three isotopes.
49. Which alkali metal react directly with Nitrogen to form nitride?
A. Na
B. K
C. Rb
D. Li
50. The isomerism which exists between CH3CHCI2 and CH2CI. CH2CI is _________.
A. chain isomerism
B. functional group isomerism
C. positional isomerism
D. metamerism
Uploaded on B. -22 kJ
C. 52 kJ
D. -52 kJ
37. Sodium peroxide dissolves in water in accordance with the following reaction:
Na2O2(s) + 2H2O(l) NaOH (aq) + H2O2(aq)
The pH of the solution after reaction will be:
A. 7-8
B. 6-7
C. < 2
D. >10
38. Gunpowder is a mixture of saltpetre, sulphur and woodcharcoal in the ratio of 6:1:1
by mass. The mixture burns with explosion because it produces a large volume of
gases. Saltpetre in the mixture acts as:
A. modifier
B. reducing agent
C. oxidising agent
D. Fuel
39. The oxidation state of Au in K[Au(OH)4] is:
A. +1
B. +2
C. +3
D. +4
40. The most common type of chemical reaction which alkanes undergo is
A. substitution
B. addition
C. condensation
D. elimination.
41. The boiling point of water is higher than that of methanol because
A. water is oxide while methanol is an alcohol
B. inter molecular forces in water are stronger than those in methanol
C. water is an inorganic compound while methanol is organic
D. water is an ionic compound while methanol is covalent
42. In the Rutherford scattering experiment, Rutherford bombarded a thin piece of gold foil
with a beam of _____.
A. electrons
B. neutrons
C. protons
D. alpha particles
Upload31. How many chiral centres does the compound below possess?
CH2CO2H
C(OH)CO2H
CH2CO2H
A. 0
B. 1
C. 2
D. 3
32. 0.200 mol of a hydrocarbon undergo complete combustion to give 35.2 g of carbon
dioxide and 14.4 g of water as the only products. What is the molecular formula of
the hydrocarbon?
A. C2H4
B. C2H6
C. C4H4
D. C4H8
33. One of the original postulates of Dalton’s Atomic Theory is:
A. An Atom reacts to attain electronic configuration of the noble gas closest to it.
B. When atoms of different elements react to form chemical compound, the atoms
are combined in simple whole number ratio.
C. The isotopes of an element are in whole number ratio.
D. Atoms of different elements differ in terms of number of protons in their nuclei.
34. The ions in a mass spectrophotometer are separated based on their mass:charge ratio
by the;
A. ion source
B. mass analyzer
C. deflector
D. detector
35. Which of the following terms accurately describes the energy associated with the
process:
Li (g)→Li+
(g) + e-
A. electron affinity
B. binding energy
C. ionization energy
D. electronegativity
36. If the activation energy in the forward direction of an elementary step is 52 kJ and the
activation energy in the reverse direction is 74 kJ, what is the energy of reaction E
for this step?

Awise001

9 months ago

i need lagos jupeb question

S2ss

12 hours ago

all question