Worksheets3 Days Workshop towards Active learning in Chemistry
Total questions: 20
Worksheet time: 26mins
Name
Class
Date
1.
The precipitate of CaF2 (Ksp = 1.7x 10-10) is obtained when equal volumes of which of the following are mixed?
a)
10-4 M Ca2+ + 10-4 M F-
b)
10-2 M Ca2+ + 10-3 M F-
c)
10-5 M Ca2+ + 10-3 M F-
d)
10-3 M Ca2+ + 10-5 M F-
2.
Positive carbylamine test is shown by
a)
N,N-dimethylaniline
b)
Triethylamine
c)
N-methylaniline
d)
p-methylabenzylamine
3.
Square planar complex of the type MABCD (where A, B, C and D are unidentate ligands) shows following sets of isomers.
a)
Two cis and one trans
b)
Two trans and one cis
c)
Two cis and two trans
d)
Three cis and one trans
4.
Which of the following cannot be used to oxidize primary alcohols to aldehydes?
a)
CrO3 in anhydrous medium
b)
Pyridinium chlorochromate
c)
KMnO4 in acidic medium
d)
Heating in the presence of Cu at 573K
5.
In the following sequence of reactions, The end product C is,
a)
Methane
b)
Ethyl alcohol
c)
Acetone
d)
Acetaldehyde
6.
The equilibrium constant for the reaction, N2 (g) + O2(g) n 2NO(g) is 4 x 10-4 at 2000 K. In presence of a catalyst, the equilibrium is attained ten times faster. Therefore, the equilibrium constant in the presence of the catalyst at 2000 K is
a)
4 x 10-3
b)
40 x 10-4
c)
4 x 10-4
d)
4 x 10-2
7.
A reaction has both ΔH and ΔS –ve. The rate of reaction
a)
Cannot be predicted for change in temperature
b)
Increases with increase in temperature
c)
Increases with decrease in temperature
d)
Remains unaffected by change in temperature
8.
Treatment of acetaldehyde with magnesium bromide and subsequent hydrolysis gives
a)
1-butanol
b)
2-butanol
c)
1-propanol
d)
tert-butanol
9.
What kind of isomerism exists between [Cr(H2O)6]Cl3 (violet) and [Cr(H2O)5Cl]Cl2.H2O (greyish-green)?
a)
Linkage isomerism
b)
Solvate isomerism
c)
Ionisation isomerism
d)
Coordination isomerism
10.
Heat of formation of acetylene is x J mol-1 and that of ethylene is y J mol-1. What is the heat of hydrogenation of acetylene?
a)
(x - y) J mol-1
b)
(x- 2y) J mol-1
c)
(y – 2x) J mol-1
d)
(y – x ) J mol-1
11.
For the process; A (l, 0.05 atm, 320C) à A (g, 0.05 atm, 320C) The correct set of thermodynamic parameters is
a)
ΔG = 0 and ΔS = -ve
b)
ΔG = 0 and ΔS = + ve
c)
ΔG = +ve and ΔS = 0
d)
ΔG = -ve and ΔS = 0
12.
Mixing of N2 and H2 form an ideal gas mixture at room temperature in a container. For this process, which of the following statements is true?
a)
ΔH = 0, ΔSsurrounding= 0, ΔSsystem = 0 and ΔG = -ve
b)
ΔH = 0, ΔSsurrounding= 0, ΔSsystem > 0 and ΔG = -ve
c)
ΔH > 0, ΔSsurrounding= 0, ΔSsystem > 0 and ΔG = -ve
d)
ΔH < 0, ΔSsurrounding > 0, ΔSsystem < 0 and ΔG = -ve
13.
Solubility product (Ksp) of saturated PbCl2 in water is 1.8 x 10-4 mol3 dm-9. What is the concentration of Pb+2 in the solution?
a)
(0.45 x 10-4)1/3 mol dm-3
b)
(1.8 x 10-4)1/3 mol dm-3
c)
(0.9 x 10-4)1/3 mol dm-3
d)
(2.0 x 10-4)1/3 mol dm-3
14.
10 g of MgCO3 decomposes on heating to 0.1 mole CO2 and 4 g MgO. The per purity of MgCO3 is
a)
54%
b)
64%
c)
74%
d)
84%
15.
The compound Na2CO3.xH2O has 50% H2O by mass . The value of ‘x’ is
a)
4
b)
5
c)
6
d)
7
16.
tert-Butyl bromide on treatment with sodium methoxide yields
a)
sodium tertiary butoxide
b)
tert-butyl methyl ether
c)
tert –butyl alcohol
d)
Iso butylene
17.
When 3 moles of the reactant A and 1 mole of the reactant B are mixed in a vessel of volume 1 L, the following reaction takes place, A(g) + B(g) 2 C (g). A(g) + B(g) If 1.5 moles of C is formed at equilibrium, the equilibrium constant (Kc) for the reaction is
a)
0.12
b)
0.50
c)
0.25
d)
4.00
18.
A mixture of gases contains H2 and O2 gases in the ration 1:4 (w/w). What is the molar ratio of the two gases in the mixture?
a)
16:1
b)
2:1
c)
1:4
d)
4:1
19.
4- Methoxy acetophenone can be prepared from anisole by
a)
Reimer –Tiemann Reaction
b)
Kolbe’s reaction
c)
Friedel- Crafts reaction
d)
Wurtz reaction
20.
At approximately what temperature does the solubility of sodium chloride, NaCl, match the solubility of potassium dichromate, K2Cr2O7?
a)
60 ºC
b)
30 ºC
c)
50 ºC
d)
83 ºC
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