ECAT Chemistry Online Test With Answers

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ECAT Chemistry Online Test

Sr. # Questions Answers Choice
1 Which one of the following reaction takes place spontaneously
2 Which statement is incorrect about standard hydrogen electrode Its oxidation and reduction potential is zero It consists of Pt wire dipped on 1 molar HCI solution The electrolyte is 1 molar NaOH solution H<sub>2</sub>gas is passes in it at 1 atmospheric pressure
3 While balancing an equation by ion electron method, the number of oxygen atoms are balanced by OH<sup>-</sup> H<sub>2</sub>O O<sub>2</sub> H<sup>+</sup>
4 Lead accumulator contains 30% NaCI solution as electrolyte 30% HCI solution as electrolyte 30% H<sub>2</sub>SO<sub>4</sub>solution as electrolyte 30% NaOH solution as electrolyte
5 In lead accumulator the electrolyte is H2SO4solution is 30% H<sub>2</sub>SO<sub>4</sub> 60% H<sub>2</sub>SO<sub>4</sub> 80% H<sub>2</sub>SO<sub>4</sub> 90% H<sub>2</sub>SO<sub>4</sub>
6 The galvanic or voltaic cells which are rechargeable called as Primary cells Secondary cells Dry cells Infinite cells
7 The voltaic or galvanic cells which cannot be recharged are called Primary cells Secondary cells Infinite cells Fuel cells
8 Electrochemical series is a list of element S arranged into the increasing order of their Standard oxidation potential Standard reduction potential Cell voltage Ionization potential
9 The value of SHE is cathode and anode is always taken to be One Zero Different Same
10 Coupling of Pb with its Pb++/Pb = -0.13 V and Ag with Ag+/ Ag = +0.80 V, the cell reaction
11 The reduction potential to copper electrode is +0.34 V and that of Zn electrode is -0.76 V. when these two are coupled the e.m.f. of the cell is -0.42 V +0.42 -1.10 V +1.10 V
12 A standard hydrogen electrode is used as standard electrode of which electrode potential is arbitrarily taken as +1 -1 0.1 Zero
13 When a metal is dipped in 1 molar of its solution at 298 K. then potential set up is called Standard electrode potential Electric charge Ionization potential Electroplating
14 The oxidation number of free element is always taken to be 0 1 2 -1
15 The function of salt bridge in the galvanic or voltaic cell is to Carry out oxidation at anode To carry out reduction at cathode Carry out electrolysis To prevent the net charge accumulation in either of the half cells
16 The cell which generates electricity as a result of spontaneous oxidation-reduction reaction is called Electrolytic cell Nelson's cell Galvanic cell Down's cell
17 The two half cells of a galvanic cell are connected by Ammeter Salt bridge Hydrogen electrode Copper electrode
18 The process of electrical coating of one metal on another to protect, decorate or to have greater resistance to corrosion is called Electroplating Electrolysis Conduction Induction
19 Purification of an impure copper is made by electrolytic cell, in which impure copper is anode and pure copper is cathode, and the electrolyte used is H<sub>2</sub>SO<sub>4</sub> CuSO<sub>4</sub> ZnSO<sub>4</sub> Na<sub>2</sub>SO<sub>4</sub>
20 Caustic soda is obtained by electrolysis of conc. aqueous solution of NaCI in a cell called Daniell's cell Nelson's cell Down's cell Voltaic cell
21 In the electrolysis of aqueous solution of sodium nitrate, the ions which are reduced at the cathode are H<sub>3</sub>O<sup>+</sup> Na<sup>+</sup> OH<sup>-</sup> NO<sup>3-</sup>
22 Metallic conduction is due to the Movement of electrons Movement of ions Both a and b None of these
23 Cell in which an electric current drives a non-spontaneous reaction is called Electrolytic cell Voltaic cell Biological cell Electrochemical cell
24 The electrolysis of CuSO4aqueous solution using copper as cathode as well an anode the substance which deposits at cathode is H<sub>2</sub>SO<sub>4</sub> Oxygen Copper Hydrogen
25 By using graphite electrode the electrolysis of aqueous solution of NaCI produces at anode H<sub>2</sub>gas Cl<sub>2</sub>gas NaOH No metal
26 When electric current is used to carry out non-spontaneous redox, the process is called Hydrolysis Electrolysis Decomposition Neutralization
27 The reaction is galvanic cell is Spontaneous Non-spontaneous Acid-base None of these
28 When fused PbBr2is electrolyzed Bromine appears at he cathode Lead is deposited at the cathode Lead appears at the anode None of these happens
29 If the salt bridge is not used between two half cells, then the voltage Decrease rapidly Decrease slowly Does not change Drops to zero
30 The electrode through which the electrons enter the electrolytic solution is electrolytic solution is Anode Cathode May be anode or cathode None of these
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