Sr. # | Questions | Answers Choice |
---|---|---|
1 | Group l-A elements react with water fastly than the reaction of group ll-A elements because | l<sub>A</sub>elements are more soft then ll<sub>A</sub> l<sub>A</sub>elements are non-metals l<sub>A</sub>elements have 1 electron in their outermost s-orbital and are strongly electropositive l<sub>A</sub>elements make ionic bond |
2 | In an experiment the concentration of a reactant 'A' is doubled the rate increases four times. If concentration in tripled, then rate increases nint times. Thus the rate is proportional to ______ of concentration of 'A' | Square root Square Twice Cube |
3 | Decreases om concentration of reactant is denoted by | dc/dt -dc/dt +dc/dt None |
4 | In thermal decomposition of N2O the half life period for two different initial concentrations of N2O are (i) 255 second for initial N2O 290 mm Hg (ii) 212 second for initial N2O 360 mm Hg then it is |
Zero order First order Second order Third order |
5 | Half life period of a reaction is inversely proportion to the initial concentration of the reactant, then order of reaction is | Third order Second order Fist order Zero order |
6 | Half life period of N2O5is 24 minutes and it remains same where we increase or decrease its initial concentration, then reactions | Zero order First order Second order Third order |
7 | 1st order 2nd order Zero order 3rd order | |
8 | Three times Six times Nine times Two times | |
9 | When we perform the same reaction by taking two different initial concentrations of a reactant for a second order reaction then | Reaction becomes exothermic Energy of activation is different Mechanism of reaction is changed Half life period is changed |
10 | Initial concentration of reaction Initial concentration of products Final concentration of products Order of the reaction | |
11 | In exothermic reaction decrease in potential energy of the products will result in | Decreases in kinetic energy of the particles Increases in kinetic energy of the particles No change in kinetic energy Decreases in activation energy |
12 | In the hydrolysis of CH3COOC2H5the acid produced is | Inhibitor Catalyst Auto catalyst None of above |
13 | By the use of catalysis the energy of activation is | Decreased Increased Not affected None |
14 | For effective collisions the molecules slow down before collision and their kinetic energy decreases which results in increase in their | Activation energy Average energy Potential energy Collisions frequency |
15 | For a chemical reaction to take place the particles must have sufficient energy for the effective collisions, the energy is called | Average energy Activation energy Potential energy Collision energy |
16 | Measuring pH Measuring density Titration against standard NaOH Titration against standard KMnO<sub>4</sub>solution | |
17 | Optical rotation method is sued when | Reaction involve ions Change of refractive indices Reactions involving change of optical activity None of the above |
18 | 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 |
19 | 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 |
20 | 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 |
21 | 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: "Times New Roman"; 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> |
22 | 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> |
23 | 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 |
24 | 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 |
25 | ||
26 | 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> | |
27 | When initial concentration of reactants an order of reaction is given, then its half life period can be calculated by the equation | |
28 | 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 |
29 | 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 |
30 | When the rate of reaction is entirely independent of the conc. of reaction molecules then order of reaction is | Zero First Second Third |