ECAT Chemistry Online Test With Answers

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ECAT Chemistry Online Test

Sr. # Questions Answers Choice
1 Optical rotation method is sued when Reaction involve ions Change of refractive indices Reactions involving change of optical activity None of the above
2 Dilatometric method is used for rate determination when Reactions involving change of optical Reactions involving change of optical activity Reactions involving small volume change None of above
3 Refrectrometric method is used when Reactions involving absorption of I.R. or U. V Reactions involving change of refractive index Reactions involving ions Change of optical activity
4 If a reactant or product of a reaction absorbs radiation, then physical method for determining the rate of reaction is Spectrometry Refractometry Conductivity measurement Optical method
5 To determine the rate of reaction chemically a graphical method is applied. A graph is plotted between the amount or reactant decomposed or product formed against the time. The rate dx/dtat any time is equal to k Tangent<span style="color: rgb(34, 34, 34); font-family: &quot;Times New Roman&quot;; font-size: 24px; text-align: center; background-color: rgb(255, 255, 224);">θ</span> 1/a, a is initial conc. 1/a<sup>2</sup>
6 The reaction rate is expressed in the units of mol dm<sup>-3</sup>S<sup>-</sup> mol dm<sup>-3</sup> mol dm<sup>-3</sup>N<sup>-</sup> dm<sup>-3</sup>S<sup>-</sup>
7 Value of rate constant k is specific for a reaction, and varies from reaction to reaction. The value of k of a reaction changes with Time Temperature Concentration of reactants Order of reaction
8 The unit of rate constant k is the same as that of the rate of reaction in First order reaction Second order reaction Third order reaction Zero order reaction
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10 Rate is independent of concentration of water since it is in excess Rate is independent of concentration of ester since it is in exces Rate depends upon the concentration of acid catalyst added Rate = k[CH<sub>3</sub>COOC<sub>2</sub>H<sub>5</sub>]<sup>1/2</sup>[H<sub>2</sub>O]<sup>1/2</sup>
11 When initial concentration of reactants an order of reaction is given, then its half life period can be calculated by the equation
12 If initial concentration of the reactants and half life period of the reaction is known, then we can determine Average rate of reaction Order of reaction Rate constant k Instantaneous rate
13 If half life period of a reaction is independent of the concentration of the reactants, then the reaction is Zero order First order Second order Order is in fraction
14 When the rate of reaction is entirely independent of the conc. of reaction molecules then order of reaction is Zero First Second Third
15 The experimental relationship between a reaction rate and the concentration of reactants is called Order or reaction Rate law Activated complex Molecularity
16 Rate = k[FeCl<sub>3</sub>] [Kl]<sup>2</sup> Rate = k[Fe<sup>+3</sup>][Cl<sup>-1</sup>] [Kl] Rate = k[Fe<sup>+3</sup>] [Cl<sup>-1</sup>][K;] Rate = k[Kl]<sup>3</sup>[FeCl<sub>3</sub>]°
17 First order Pseudo first order Second order Zero order
18 Zero 1 2 1.5
19 The rate of reaction is denoted by dc/dp dc/ac dc/dT dc/dt
20 The sum of the exponents of the conc. terms in the rate equation is called Rate of reaction Order of reaction Specific rate constant Average rate
21 In the hydrolysis of CH3COOC2H5the acid produced is Inhibitor Catalyst Auto catalyst None of above
22 The rate of reaction between two specific time intervals is called Instantaneous rate Average rate Specific rate Ordinary rate
23 The rate of reaction determined at a given time is called Average rate Instantaneous rate Specific rate Overall rate
24 In the rate equation when the concentration of reactants are unity, then rate is equal to Instantaneous rate Average rate Active mass of products Specific rate constant
25 Small change in concentration of product Small time internal Co-efficient of the reactant Co-efficient of the product
26 The unit of rate of reaction is mole dm<sup>-3</sup> mole Kg<sup>-1</sup> moles dm<sup>-3</sup>sec<sup>-1</sup> grams dm<sup>-3</sup>
27 Which statement is not correct Enzymes catalyst a specific reaction Enzymes show catalytic activity at a specific temperature The catalytic activity of enzymes is stopped if optimum pH is changed The catalytic activity is poisoned by a co-enzymes
28 A substance which increases the rate of a reaction without being consumed during the reaction is called An autocatalyst A catalyst A negative catalyst All of these
29 Factor which slows down the rate of reaction is Small size of the particles of the reactant High temperature of reaction More concentration of reactant Lowering the temperature
30 Activation energy is the difference of energy between the energy of the reactant and The product The activated complex Both a and b None of these
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