Welcome to your chemistry 2007
1.
According to valence bond theory. Which orbitals on bromine atoms overlap in the formation of the bond in Br2?
2.
The type of compound that is most likely to contain a covalent bond is one that is
3.
The first step of the scientific method involves
4.
The process of solute particles being surrounded by solvent particles is known as
5.
Which one of the following represents an acceptable possible set of quantum numbers (in the order n, l, ml, ms) for an electron in an atom?
6.
Of the three types of radioactivity characterized by Rutherford, which of the following are particles?
7.
Which kind of energy is converted in a galvanic cell?
8.
The conversion of nitrogen gas to nitrates by bacteria is called
9.
According to the Arrhenius concept, an acid is a substance that
10.
A system which can exchange both matter and energy with its surroundings is said to be a/an
11.
At which point can only the solid and liquid phases coexist in the phase diagram of water given below?
12.
What type of solute-solvent interaction should be the most important in a solution of iodine in carbon tetrachloride?
13.
The distance between tow carbon atoms in a diamond is 154pm. What is the distance between the carbon atoms in millimetres?
14.
For the acid-base equilibrium.
15.
How many sigma and Pi bonds are present in the following molecule?
16.
How many orbital are there in an atom with n = 4?
17.
The most abundant metal on the surface of the earth is
18.
Which of the following is correct?
19.
The enthalpy of combustion of solid carbon to form carbon dioxide is 393.5kJ/mol carbon and the enthalpy of combustion of carbon monoxide to form carbon dioxide is -283.3kJ/mol CO. what will be the enthalpy change. ∆H for the reaction?
20.
The decreasing order of electrochemical characteristics of some metals is given as: Mg > Al > Zn > Cu > Ag. What will happen if a copper spoon is used to stir a solution of aluminium nitrate (Al(NO3))3 ?
21.
What hybridization change does the carbon atom undergo in the combustion of methane?
22.
Which of the following ionic compounds has the greatest lattice energy?
23.
Condider the three electromagnetic waves shown below Which of the electromagnetic waves has the highest frequency?
24.
Considering the reaction below, in which of the following will the effect of concentration and temperature simultaneously cause an increase in the rate at which products are formed?
25.
Which of the following diagrams describes the electron density in the dxy orbital?
26.
The wave number of an electromagnetic radiation is 1 x 105cm-1. The frequency of the radiation would be
27.
For the gas phase reaction
28.
In the reaction (2SO2+ O2 ⇌ 2SO3, Keq = 100). What will be the concentration of O2, if the concentration of SO2 is the same as that of SO3?
29.
The decomposition of nitrosyl chloride was studied as
30.
Considering the mechanism for a reaction below, which of the following statements is correct?
31.
The acid-base indicator bromocresol green is a weak acid. The yellow acid and blue base forms of the indicator are present in equal concentrations in a solution when the PH is 4.68. What is the PKa of bromocresol green?
32.
If NaNO2 is added to a solution of HNO2, which of the following statements is true?
33.
A lipid is any substance of biochemical origin that is
34.
A solution in an electrolytic cell contains Cu2+ (E0 = 0.34V), Ag+ (E0 = 0.80V), and Zn2+ (E0 = 0.76V). If the voltage is initially very low and slowly increased, in which order will the metals be plated out on to the cathode?
35.
What is the concentration of sodium chloride in water needed in order to produce an aqueous solution that has an identical osmotic pressure (Isotonic) with blood (π = 7.70 atm at 250C)?
36.
What is the molality of a 5g hydrogen peroxide (H2O2) in 100mL solution that is used for hair bleaching?
37.
The maximum number of electrons in P-orbital with n = 6, ml = 0 is
38.
How many unpaired electrons are there in the Lewis structure of a N3- ion?
39.
Which one of the following metals is extracted by thermal reduction process?
40.
Which of the following transitions will emit maximum energy in the hydrogen atom?
41.
what is the IUPAC name for the compound
42.
The connectional equilibrium constant expression (Kc) for the system
43.
Which of the following compound does NOT follow the octet rule?
44.
Chemically, fats and oils are
45.
The reaction A + 3B = 2C + D is first order with respect to reactant A and second order with respect to reactant B. if the concentration of A is doubled and the concentration of B is halved, the rate of the reaction would by a factor of .
46.
The molecular geometry of H3O+ ion is
47.
If a student wishes to prepare approximately 100milliters of an aqueous solution of 6M HCl using 12M HCl, which procedure is correct?
48.
What is the final concentration of Cl- ion when 250ml of 0.20M CaCl2 solution is mixed with 250ml of 0.4M KCl solution? (Assume additive volumes)
49.
Which of the following is used in the reaction called saponification?
50.
The concentration of nitrate ion in a solution that contains 0.900M aluminium nitrate is
51.
Electrolysis of dilute aqueous NaCl solution was carried out by passing 10 milliampere current. The time required to liberate 0.01 mol of H2 gas at the cathode is
52.
How many electrons will appear when the following half-reaction is balanced?
53.
PKa values of three acids x, y and z are 4.5, 3.5 and 6.5, respectively. Which of the following represents the correct order of acid strength?
54.
Standard electrode potential for Sn4+/Sn2+ couple is +0.15V and that for the Cr3+/Cr couple is -0.74V. These two couples in their standard state are connected to make a spontaneous reaction. The cell potential will be
55.
The enthalpies of formation of gaseous N2O and NO at 298K are 82 and 90KJ/mol, respectively. The enthalpy change for the reaction N2O (g) + 1/2 O2 (g) → 2NO (g) is
56.
The following data were collected at the end point of a titration performed to find the molarity of an HCl solution.
57.
The hybridization of the central atom in the XeF4 molecule is
59.
Bakelite is obtained from phenol by reacting with
60.
In which one of the following numbers are all of the zeros significant?
61.
An aqueous solution contains 0.100M NaOH at 25.00C. The PH of the solution is?
62.
The solubility of oxygen gas in water at 250C and 1.0 atm pressure of oxygen is 0.41g/L. the solubility of oxygen in water at 3.0 atm and 250C is g/L.
63.
The decomposition of carbon disulphide, CS2, to carbon mono sulphide, CS, and sulphur is first order with K = 2.8 x 10-7 s-1 at 10000C. What is the half-life of the reaction below at 10000C?
64.
The PKa of a weak monoprotic acid is 4.8. What should be the ratio of [Acid]/[Salt] of a buffer, if PH = 5.8 is required?
65.
The dissolution of water in octane (C8H18) is prevented by
66.
At 4450C, Kc for the following reaction is 0.020.
67.
Natural rubber is a polymer of
68.
Which of the following statements is true?
69.
If the enthalpy change for a certain reaction A → B is -2KJ at 300K, what would be the entropy change in the surroundings?
70.
During the electrolysis of an aqueous solution of copper sulphate using platinum electrodes, the reaction takes place at the anode is
71.
What is the major product of the reaction?
72.
Which of the following is an acceptable IUPAC name for the organic compound shown below?
73.
Which of the following molecules has a dipole moment?
74.
Which of the following describes the balanced molecular equation when perchloric acids is mixed with solid iron (III) hydroxide?
75.
At 298 K the following two gaseous equilibrium involving SO2 SO3 and O2 are established.
76.
A compound is formed by the combination of V and X as follows. What is empirical formula for the compound?
77.
H for solid to liquid transitions for compound A is 2.73Kcal/mol and for compound B is 3.0 Kcal/mol. The melting point for compound A is 00C and the melting point for compound B is 300C. the entropy changes ∆SA and ∆SB at the two transition temperatures are related as
78.
Which of the following metals forms a volatile compound that is taken as an advantage for its extraction?
79.
A 0.1M solution of HCl is dissolved in water. What species of ions are present at equilibrium, and what will be their equilibrium concentrations?
80.
The following bases and their conjugate acids (as the chlorides) are available in the laboratory: NH3(Kb = 1.8 x 10-5), C6H5NCH3CH2NH2(Kb = 6.4 x 10-4) and CH3NH2 (Kb = 4.4 x 10-4). Which of these acid-base pairs are the best to prepare a buffer solution having a PH of about 9?
