12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications மின்னணு தரவு பரிமாற்றம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிக பாதுகாப்பு அமைப்புகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின்னணு செலுத்தல் முறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications மின் - வணிகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications திறந்த மூல கருத்துருக்கள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications வலையமைப்பு வடமிடல் Sample Question Papers Study Material - QB365 Set A
Published on: 13/10/2020
12th Standard Chemistry Electro Chemistry English Medium Free Online Test One Mark Questions with Answer Key 2020 - 2021
Download Tamil Nadu 12th Standard Chemistry question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Chemistry Test
1.
SHE is _______.
Standard Helium Electrode
Standard Hydrogen Electrode
Standard Mercury Electrode
none of these
2.
The electrode where there is gain of electrons is called ______.
cathode
anode
electrode
both anode and electrode
3.
_______ is the reciprocal of resistance.
specific conductance
molar conductance
specific resistance
conductance
4.
Debye constants A and B depend on ______.
nature of the solvent
temperature
concentration of the solvent
both nature of the solvent and temperature
5.
When a zinc metal strip is placed in a copper sulphate solution the blue colour of the solution fades and copper is deposited on the zinc strip as red - brown crust. The oxidation half cell reaction of the above process is represented as _______.
Cu2+(aq) + 2e- ⟶ Cu(s)
Cu(s) ⟶ Cu2++ 2e-
Zn(S) ⟶ Zn2+(aq) + 2e-
Zn2+(aq) + 2e- ⟶ Zn(s)
6.
Leclanche cell is ______.
primary battery
secondary battery
rechargeable
both secondary battery and rechargeable
7.
The quantity of charge required to obtain 1 mole of aluminum from Al2O3 is ______.
2F
3F
6F
12F
8.
The standard conditions for determination of standard emf of the cell are ______.
1M solution of the reactant
temperature of 25°C
both 1M solution of the reactant and temperature of 25°C
none of these
9.
For the given cell Cr(s)|Cr3+(aq)||Cu2+(aq)|Cu(s) which is correct?
Cr is the anode
Cu is the anode
Overall cell reaction is 2Cr3+(aq) +3Cu(s) ⟶ 2Cr(s) + 3Cu2+(aq)
Cu is the anode and Overall cell reaction is 2Cr3+(aq) +3Cu(s) ⟶ 2Cr(s) + 3Cu2+(aq)
10.
The laws of electrolysis were enunciated first by
Dalton
Faraday
Kekule
Avogadro
11.
Kohlrausch's law is applied to calculate ________.
molar conductance at infinite dilution of a weak electrolyte
degree of dissociation of weak electrolyte
solubility of a sparingly soluble salt
all the above
12.
Which of the statements about electrolytic conductance is not true?
Conductivity increases with decrease in viscosity.
Higher dielectric constant shows lower conductance in solution.
Temperature increases, conductance also increases.
Molar conductance increases with increase in dilution.
13.
Pick out the correct statement regarding resistance of an electrolytic solution ________.
It is inversely proportional to the length (I)
It is inversely proportional to the cross sectional area (A)
It is directly proportional to the cross sectional area (A)
Resistivity is denoted by p (rho)
14.
A gas X at 1 atm is bubbled through a solution containing a mixture of 1MY- and 1MZ- at 25oC. If the reduction potential of Z>Y>X, then_____.
Y will oxidize X and not Z
Y will oxidize Z and not X
Y will oxidize both X and Z
Y will reduce both X and Z
15.
In the electrochemical cell: Zn|ZnSO4 (0.01M)|| CuSO4 (1.0M)|Cu, the emf of this Daniel cell is E1. When the concentration of ZnSO4 is changed to 1.0M and that CuSO4 changed to 0.01M, the emf changes to E2. From the above, which one is the relationship between E1 and E2?
E1 < E2
E1 > E2
E2 ≥ E1
E1 = E2
16.
In H2-O2 fuel cell the reaction occur at cathode is _______.
O2(g) + 2H2O(l) + 4e- ⟶ 4OH− (aq)
H+(aq) + OH− (aq) ⟶ H2O (l)
2H2 (g) + O2 (g) ⟶ 2H2O (g)
H+ + e- ⟶ 1/2 H2
17.
While charging lead storage battery _______.
PbSO4 on cathode is reduced to Pb
PbSO4 on anode is oxidised to PbO2
PbSO4 on anode is reduced to Pb
PbSO4 on cathode is oxidised to Pb
18.
The number of electrons delivered at the cathode during electrolysis by a current of 1A in 60 seconds is ____. (charge of electron = 1.6 ×10−19C )
6.22 ×1023
6.022 ×1020
3.75 ×1020
7.48 ×1023
19.
Faraday constant is defined as_______.
charge carried by 1 electron
charge carried by one mole of electrons
charge required to deposit one mole of substance
charge carried by 6.22 ×1010 electrons
20.
Consider the following half cell reactions.
Mn2+ + 2e- ➝ Mn Eo = -1.18V
Mn2+ ➝ Mn3+ + e- Eo = -1.51V
The Eo for the reaction 3Mn2+➝ Mn + 2Mn3+, and the possibility of the forward reaction are respectively.
2.69V and spontaneous
-2.69 and non spontaneous
0.33V and Spontaneous
4.18V and non spontaneous
1.
(b)
Standard Hydrogen Electrode
2.
(a)
cathode
3.
(d)
conductance
4.
(d)
both nature of the solvent and temperature
5.
(c)
Zn(S) ⟶ Zn2+(aq) + 2e-
6.
(a)
primary battery
7.
(b)
3F
8.
(c)
both 1M solution of the reactant and temperature of 25°C
9.
(a)
Cr is the anode
10.
(b)
Faraday
11.
(d)
all the above
12.
(b)
Higher dielectric constant shows lower conductance in solution.
13.
(b)
It is inversely proportional to the cross sectional area (A)
14.
Z is tie strongest oxidising agent (High SRP)
X is the strongest reducing agent (Low SRP)
15.
Ecell = Eocell - \(\frac{0.0591}{2} \log [\frac{Zn^{2+}}{Cu^{2+}}]\)
El = Eocell - \(\frac{0.0591}{2} \log [\frac{10^{-2}}{1}]\)
El = Eocell + 0.0591 ...(1)
E2 = Eocell - \(\frac{0.0591}{2} \log [\frac{1}{10^{-2}}]\)
E2 = Eocell - 0.0591 ...(2)
E1 > E2
Zn(s)| ⟶ Zn2+(aq) + 2e-
Cu2+(aq) + 2e- ⟶ Cu(s)
Zn(s) + Cu2+(aq) ⟶ Zn2+(aq) + Cu(s)
16.
(a)
O2(g) + 2H2O(l) + 4e- ⟶ 4OH− (aq)
17.
Charging anode:
PbSO4(s) + 2e- ➝ Pb(s) + SO42-(aq)
Cathode:
PbSO4(s) + 2H2O(I) ➝ PbO2(s) + SO42-(aq) + 2e-
18.
Q = It
= 1A x 60s = 60 C
96500 C charge = 6.023 x 1023 electrons
60 C charge \(= \frac{6.023 \times 10^{23}}{96500}\times 60\)
= 3.744 x 1020 electrons
19.
IF = 96500 C = charge of one mole of e- charge of 6.022 x 10-23 electron
20.
Mn2+ + 2e- ➝ Mn Eo = -1.18V
Mn2+ ➝ Mn3+ + e- Eo = -1.51V
3Mn2+➝ Mn3+ + 2Mn3+ Eocell = ?
Eocell = (Eoox )+ (Eored)
= 1.51 - 1.18 and non spontaneous
= -2.69V
Since E°is ve ΔG is +ve and the given forward cell reaction is non- spontaneous
12th Standard Syllabus & Materials
12th Standard
TN 12th Computer Applications களப்பெயர் முறைமை (DNS) Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications வலையமைப்பு எடுத்துக்காட்டுகள் மற்றும் நெறிமுறைகள் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications கணினி வலையமைப்பு ஓர் அறிமுகம் Sample Question Papers Study Material - QB365 Set A
NEW12th Standard
TN 12th Computer Applications PHP-உடன் MySQL-ஐ இணைத்தல் Sample Question Papers Study Material - QB365 Set A
Tamilnadu Stateboard 12th Standard Subjects
Maths
Chemistry
Physics
Biology
Computer Science
Business Maths and Statistics
Economics
Commerce
Accountancy
History
Computer Applications
Biology
Computer Technology
Computer Applications
Computer Science
Business Maths and Statistics
Commerce
Economics
Maths
Chemistry
Physics
Computer Technology
History
Accountancy
Tamil
English
French
Tamilnadu Stateboard Standards
