The increasing order of basicity of the following compounds is :
Answer
(D)
(b) < (a) < (d) < (c)
2
An alkali is titrated against an acid with methyl orange as indicator, which of the following is a correct combination?
Answer
(C)
Base
Acid
End point
Weak
Strong
Yellow to pinkish red
3
The predominant form of histamine present in human blood is (pKa, Histidine = 6.0)
Answer
(A)
4
Glucose on prolonged heating with HI gives
Answer
(B)
n-Hexane
5
The major product formed in the following reaction is :
Answer
(A)
6
Phenol reacts with methyl chloroformate in the presence of NaOH to form product A. A reacts with Br2 to
form product B. A and B are respectively :
Answer
(D)
7
Phenol on treatment with CO2 in the presence of NaOH followed by acidification produces compound X as
the major product. X on treatment with (CH3CO)2O in the presence of catalytic amount of H2SO4 produces:
Answer
(B)
8
The trans-alkenes are formed by the reduction of alkynes with
Answer
(D)
Na/liq. NH3
9
The major product of the following reaction is:
Answer
(C)
10
Which of the following compounds will be suitable for Kjeldahl’s method for nitrogen estimation?
Answer
(C)
11
The compound that does not produce nitrogen gas by the thermal decomposition is :
Answer
(A)
(NH4)2SO4
12
The oxidation states of Cr in [Cr(H2O)6]Cl3, [Cr(C6H6)2] and K2[Cr(CN)2(O)2(O2)(NH3)] respectively are :
Answer
(D)
+3, 0 and +6
13
Consider the following reaction and statements:
[Co(NH3)4Br2]+ + Br- $$\to$$ [Co(NH3)3Br3] + NH3
(I) Two isomers are produced if the reactant complex ion is a cis-isomer
(II) Two isomers are produced if the reactant complex ion is a trans-isomer
(III) Only one isomer is produced if the reactant complex ion is a trans-isomer
(IV) Only one isomer is produced if the reactant complex ion is a cis – isomer
The correct statements are
Answer
(C)
(I) and (III)
14
Which of the following compounds contain(s) no covalent bond(s)?
KCl, PH3, O2, B2H6, H2SO4
Answer
(D)
KCl
15
How long (approximate) should water be electrolysed by passing through 100 amperes current so that the
oxygen released can completely burn 27.66 g of diborane?
(Atomic weight of B = 10.8 u)
Answer
(D)
3.2 hours
16
At 518oC the rate of decomposition of a sample of gaseous acetaldehyde initially at a pressure of 363 Torr,
was 1.00 Torr s–1 when 5% had reacted and 0.5 Torr s–1 when 33% had reacted. The order of the reaction is
Answer
(B)
2
17
Which of the following salts is the most basic in aqueous solution?
Answer
(C)
CH3COOK
18
Which of the following are Lewis acids?
Answer
(A)
BCl3 and AlCl3
19
An aqueous solution contains 0.10 M H2S and 0.20 M HCl. If the equilibrium constants for the formation of HS– from H2S is 1.0 $$\times$$ 10–7 and that of S2- from HS– ions is 1.2 $$\times$$ 10–13 then the concentration of S2- ions in aqueous solution is :
Answer
(C)
3 $$\times$$ 10–20
20
An aqueous solution contains an unknown concentration of Ba2+. When 50 mL of a 1 M solution of Na2SO4 is added, BaSO4 just begins to precipitate. The final volume is 500 mL. The solubility product of BaSO4 is 1 $$\times$$ 10–10. What is the original concentration of Ba2+?
Answer
(D)
1.1 $$\times$$ 10–9 M
21
For 1 molal aqueous solution of the following compounds, which one will show the highest freezing
point?
Answer
(A)
[Co(H2O)3 Cl3].3H2O
22
Which of the following lines correctly show the temperature dependence of equilibrium constant K, for an
exothermic reaction?
Answer
(B)
A and B
23
The combustion of benzene(l) gives CO2(g) and H2O(l). Given that heat of combustion of benzene at constant volume is –3263.9 kJ mol–1 at 25oC; heat of combustion (in kJ mol–1) of benzene at constant pressure will be :
(R = 8.314 JK–1 mol–1)
Answer
(A)
–3267.6
24
Total number of lone pair of electrons in $${\rm I}_3^ - $$ ion is
Answer
(B)
9
25
According to molecular orbital theory, which of the following will not be a viable molecule?
Answer
(D)
$${\rm H}_2^{2 - }$$
26
The ratio of mass percent of C and H of an organic compound (CXHYOZ) is 6 : 1. If one molecule of the above compound (CXHYOZ) contains half as much oxygen as required to burn one molecule of compound CXHY completely to CO2 and H2O. The empirical formula of compound CXHYOZ is