Ethylene glycol is used as an antifreeze in a cold climate. Mass of ethylene glycol which should be
added to 4 kg of water to prevent it from freezing at −6oC will be :
[Kf for water = 1.86 K kg mol−1 , and molar mass of ethylene glycol = 62 g mol−1 )
Trả lời
(D)
804.32 g
2
A 5.2 molal aqueous solution of methyl alcohol, CH3OH, is supplied. What is the mole fraction of methyl
alcohol in the solution ?
Trả lời
(B)
0.086
3
Ozonolysis of an organic compound gives formaldehyde as one of the products. This confirms the
presence of :
Trả lời
(A)
a vinyl group
4
Identify the compound that exhibits tautomerism.
Trả lời
(B)
2-Pentanone
5
A vessel at 1000 K contains CO2 with a pressure of 0.5 atm. Some of the CO2 is converted into CO on
the addition of graphite. If the total pressure at equilibrium is 0.8 atm, the value of K is :
Trả lời
(D)
1.8 atm
6
The entropy change involved in the isothermal reversible expansion of 2 moles of an ideal gas from a
volume of 10 dm3 to a volume of 100 dm3 at 27oC is :
Trả lời
(D)
38.3 J mol-1 K−1
7
The degree of dissociation ($$\alpha$$ ) of a weak electrolyte, AxBy is related to van’t Hoff factor (i) by the expression :
Trả lời
(D)
$$\alpha = {{i - 1} \over {(x + y - 1)}}$$
8
Trichloroacetaldehyde was subjected to Cannizzaro’s reaction by using NaOH. The mixture of the
products contains sodium trichloroacetate and another compound. The other compound is :
Trả lời
(D)
2, 2, 2-Trichloroethanol
9
The outer electron configuration of $$Gd$$ (Atomic No. $$64$$) is :
Trả lời
(D)
$$4{f^7}\,5{d^1}\,6{s^2}$$
10
Outer electronic configuration of Gd (Atomic no : 64) is -
Trả lời
(C)
4f75d16s2
11
The presence or absence of hydroxyl group on which carbon atom of sugar differentiates RNA and DNA ?
Trả lời
(A)
2nd
12
Silver Mirror test is given by which one of the following compounds ?
Trả lời
D
B
13
Sodium ethoxide has reacted with ethanoyl chloride. The compound that is produced in the above
reaction is
Trả lời
(C)
Ethyl ethanoate
14
The strongest acid amongst the following compounds is :
Trả lời
(B)
CH3CH2CH(Cl)CO2H
15
Which of the following reagents may be used to distinguish between phenol and benzoic acid ?
Trả lời
(C)
Neutral FeCl3
16
Phenol is heated with a solution of mixture of KBr and KBrO3. The major product obtained in the above
reaction is
Trả lời
(C)
2, 4, 6- Tribromophenol
17
The magnetic moment (spin only) of [NiCl4]2− is
Trả lời
(B)
2.82 BM
18
Which of the following facts about the complex [Cr (NH3)6 ]Cl3 is wrong?
Trả lời
(B)
The complex is an outer orbital complex
19
In context of the lanthanoids, which of the following statements is not correct?
Trả lời
(C)
Availability of 4f electrons results in the formation of compounds in +4 state for all the members
of the series.
20
Which of the following statements regarding sulphur is incorrect?
Trả lời
(C)
The oxidation state of sulphur is never less than +4 in its compounds
21
Which of the following statement is wrong?
Trả lời
(D)
The stability of hydrides increases from NH3 to BiH3 in group 15 of the periodic table
22
The rate of a chemical reaction doubles for every 10oC rise of temperature. If the temperature is raised
by 50oC , the rate of the reaction increases by about :
Trả lời
(B)
32 times
23
The reduction potential of hydrogen half cell will be negative if :
Trả lời
(C)
p(H2) = 2 atm and [H+] =1.0 M
24
The structure of IF7 is :
Trả lời
(C)
pentagonal bipyramid
25
The hybridization of orbitals of N atom in $$NO_3^-$$, $$NO_2^+$$ and $$NH_4^+$$ are respectively :
Trả lời
(B)
sp2, sp , sp3
26
Among the following the maximum covalent character is shown by the compound :
Trả lời
(B)
AlCl3
27
Which one of the following order represents the correct sequence of the increasing basic nature of the
given oxides ?
Trả lời
(B)
Al2O3 < MgO < Na2O < K2O
28
A gas absorbs a photon of 355 nm and emits at two wavelengths. If one of the emissions is at
680 nm, the other is at :
