A piston filled with 0.04 mol of an ideal gas expands reversibly from 50.0 mL to 375 mL at a constant
temperature of 37.0oC. As it does so, it absorbs 208J of heat. The values of q and w for the process will be :
(R = 8.314 J/mol K) ( l n 7.5 = 2.01)
إجابة
(D)
q = + 208 J, w = – 208 J
2
How many litres of water must be added to 1 litre of an aqueous solution of HCl with a pH of 1 to create an
aqueous solution with pH of 2?
إجابة
(D)
9.0 L
3
A compound with molecular mass 180 is acylated with CH3COCl to get a compound with molecular mass
390. The number of amino groups present per molecule of the former compound is:
إجابة
(B)
5
4
An organic compound A upon reacting with $$N{H_3}$$ gives $$B.$$ On heating $$B$$ gives $$C.$$ $$C$$ in presence of $$KOH$$ reacts with $$B{r_2}$$ to given $$C{H_3}C{H_2}N{H_2}2.$$ $$A$$ is :
إجابة
(D)
$$C{H_3}C{H_2}COOH$$
5
Arrange the following compounds in order of decreasing acidity :
Compound $$\left( A \right),\,{C_8}{H_9}Br,\,\,\,$$ gives a white precipitate when warmed with alcoholic $$AgN{O_3}.$$ Oxidation of $$(A)$$ gives an acid $$\left( B \right),$$ $${C_8}{H_6}{O_4}.\,\,\left( B \right)$$ easily forms anhydride on heating. Identify the compound $$(A).$$
إجابة
(D)
7
The order of stability of the following carbocations :
Synthesis of each molecule of glucose in photosynthesis involves:
إجابة
(D)
18 molecules of ATP
9
The gas leaked from a storage tank of the Union Carbide plant in Bhopal gas tragedy was:
إجابة
(D)
Methyl isocyanate
10
An unknown alcohol is treated with the “Lucas reagent” to determine whether the alcohol is primary,
secondary or tertiary. Which alcohol reacts fastest and by what mechanism:
إجابة
(A)
tertiary alcohol by SN1
11
Which of the following complex species is not expected to exhibit optical isomerism?
إجابة
(B)
[Co (NH3)3 Cl3]
12
Four successive members of the first row transition elements are listed below with atomic numbers. Which
one of them is expected to have the highest $$E_{{M^{3 + }}/{M^{2 + }}}^0$$ value?
إجابة
(C)
Co (Z = 27)
13
Which of the following arrangements does not represent the correct order of the property stated against it?
إجابة
(D)
V2+ < Cr2+ < Mn2+ < Fe2+ : paramagnetic behaviour
14
The rate of a reaction doubles when its temperature changes from 300K to 310K. Activation energy of such
a reaction will be:(R = 8.314 JK–1 mol–1 and log 2 = 0.301)
Based on the data given above, strongest oxidising agent will be :
إجابة
(C)
$$MnO_4^ - $$
16
The molarity of a solution obtained by mixing 750 mL of 0.5 (M) HCl with 250 mL of 2(M) HCl will be:
إجابة
(D)
0.875 M
17
A solution of (–$$l$$) – chloro –1 – phenylethane in toluene racemises slowly in the presence of a small
amount of SbCl5, due to the formation of :
إجابة
(B)
carbocation
18
Stability of the species Li2, $$Li_2^−$$ and $$Li_2^+$$ increases in the order of:
إجابة
(C)
$$Li_2^-$$ <$$Li_2^+$$ < Li2
19
In which of the following pairs of molecules/ions, both the species are not likely to exist?
إجابة
(C)
$$H_2^{2+}$$ , $$He_2$$
20
Which one of the following molecules is expected to exhibit diamagnetic behaviour?
إجابة
A
D
21
The first ionization potential of Na is 5.1 eV. The value of electron gain enthalpy of Na+
will be:
إجابة
(A)
– 5.1 eV
22
Which of the following represents the correct order of increasing first ionization enthalpy for Ca, Ba, S, Se
and Ar?
إجابة
(B)
Ba < Ca < Se < S < Ar
23
Energy of an electron is given by $$E = - 2.178 \times {10^{ - 18}}J\left( {{{{Z^2}} \over {{n^2}}}} \right)$$. Wavelength of light required to excite an
electron in an hydrogen atom from level n = 1 to n = 2 will be
(h = 6.62 × 10−34 Js and c = 3.0 × 108 ms−1)
إجابة
(D)
1.214 × 10−7 m
24
Experimentally it was found that a metal oxide has formula M0.98O. Metal M, present as M2+ and M3+ in its oxide. Fraction of the metal which exists as M3+ would be
إجابة
(B)
4.08%
25
A gaseous hydrocarbon gives upon combustion 0.72 g of water and 3.08 g of CO2. The empirical formula of the hydrocarbon is
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