MCQOPTIONS
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MCQOPTIONS
This section includes 1443 Mcqs, each offering curated multiple-choice questions to sharpen your Chemical Engineering knowledge and support exam preparation. Choose a topic below to get started.
| 1251. |
Which of the following is used for calcination of limestone and dolomite in industrial practice? |
| A. | Fluidised bed reactor |
| B. | Moving bed reactor |
| C. | Fixed bed reactor |
| D. | None of these |
| Answer» C. Fixed bed reactor | |
| 1252. |
Velocity of a chemical reaction |
| A. | Decreases with increase in temperature |
| B. | Increases with increase of pressure of reactants for all reactions |
| C. | Decreases with increase of reactant concentration |
| D. | None of these |
| Answer» E. | |
| 1253. |
Fractional conversion __________ with increase in pressure for ammonia synthesis reaction i.e., N2 + 3H2 ⇌ 2NH3. |
| A. | Increases |
| B. | Decreases |
| C. | Remains unchanged |
| D. | Unpredictable from the data |
| Answer» B. Decreases | |
| 1254. |
Shift conversion reaction |
| A. | Converts N2 and H2 into NH3 |
| B. | Converts CO to CO2 with steam |
| C. | Is non-catalytic |
| D. | Is highly exothermic |
| Answer» C. Is non-catalytic | |
| 1255. |
A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant). |
| A. | ∝ CA |
| B. | ∝ 1/CA |
| C. | Independent of temperature |
| D. | None of these |
| Answer» E. | |
| 1256. |
Find a mechanism that is consistent with the rate equation and reaction given below: 2A + B → A2B, ( - rA) = k.CA.CB |
| A. | A + B ⇌ AB; AB + A → A2B |
| B. | A + B → AB; AB + A → A2B |
| C. | A + A → AA; AA + B → A2B |
| D. | A + A ⇌ AA; AA + B → A2B |
| Answer» E. | |
| 1257. |
In a semi-batch reactor |
| A. | Velocity of reaction can be controlled |
| B. | Maximum conversion can be controlled |
| C. | Both the reactants flow counter-currently |
| D. | Residence time is constant |
| Answer» B. Maximum conversion can be controlled | |
| 1258. |
According to the 'law of mass action', the rate of reaction is directly proportional to the |
| A. | Equilibrium constant |
| B. | Volume of the reaction vessel |
| C. | Nature of the reactants |
| D. | Molar concentration of the reactants |
| Answer» E. | |
| 1259. |
The catalytic converter for conversion of SO2 to SO3 by contact process should have a feed with SO2 content between |
| A. | 2-5 % |
| B. | 7-10 % |
| C. | 12-15 % |
| D. | 20-25 % |
| Answer» C. 12-15 % | |
| 1260. |
For a first order chemical reaction in a porous catalyst, the Thiele modulus is 10. The effectiveness factor is approximately equal to |
| A. | 0 |
| B. | 1 |
| C. | 0.1 |
| D. | 0.5 |
| Answer» D. 0.5 | |
| 1261. |
With an increase in pressure in gaseous phase chemical reactions, the fractional conversion __________ when the number of moles decreases. |
| A. | Increases |
| B. | Decreases |
| C. | Remain unaffected |
| D. | Unpredictable from the data |
| Answer» B. Decreases | |
| 1262. |
The rate constant of a chemical reaction increases by 100 times when the temperature is increased from 400 °K to 500 °K. Assuming transition state theory is valid, the value of „E/R’ is |
| A. | 8987°K |
| B. | 9210°K |
| C. | 8764°K |
| D. | 8621°K |
| Answer» C. 8764°K | |
| 1263. |
Most important characteristics of gas-liquid reactors are the |
| A. | Specific inter-facial area |
| B. | Liquid hold-up |
| C. | Both (A) and (B) |
| D. | None of these |
| Answer» D. None of these | |
| 1264. |
The reaction between oxygen and organic material is a/an __________ reaction |
| A. | Exothermic |
| B. | Endothermic |
| C. | Biochemical |
| D. | Photochemical |
| Answer» B. Endothermic | |
| 1265. |
For the reaction, A + B → 2B + C, |
| A. | rA = rB |
| B. | rA = -rB |
| C. | rA = 2rB |
| D. | rA = rB/2 |
| Answer» C. rA = 2rB | |
| 1266. |
Which of the following is not a theory of homogeneous reaction? |
| A. | Collision theory and activated complex theory |
| B. | Chain reaction theory |
| C. | Radiation hypothesis |
| D. | None of these |
| Answer» E. | |
| 1267. |
The reaction rate constants at two different temperatures T1 and T2 are related by |
| A. | ln (k2/k1) = (E/R) (1/T2 - 1/T1) |
| B. | ln (k2/k1) = (E/R) (1/T1 - 1/T2) |
| C. | exp (k2/k1) = (E/R) (1/T2 - 1/T1) |
| D. | exp (k2/k1) = (E/R) (1/T1 - 1/T2) |
| Answer» C. exp (k2/k1) = (E/R) (1/T2 - 1/T1) | |
| 1268. |
6 gm of carbon is burnt with an amount of air containing 18 gm oxygen. The product contains 16.5 gms CO2 and 2.8 gms CO besides other constituents. What is the degree of conversion on the basis of disappearance of limiting reactant? |
| A. | 100% |
| B. | 95% |
| C. | 75% |
| D. | 20% |
| Answer» C. 75% | |
| 1269. |
The size of plug flow reactor (PFR) for all positive reaction orders and for any given duty, is __________ that of mixed reactor. |
| A. | Greater than |
| B. | Equal to |
| C. | Smaller than |
| D. | Unpredictable from the data |
| Answer» D. Unpredictable from the data | |
| 1270. |
A first order reaction requires two equal sized CSTR. The conversion is |
| A. | Less when they are connected in series |
| B. | More when they are connected in series |
| C. | More when they are connected in parallel |
| D. | Same whether they are connected in series or in parallel |
| Answer» C. More when they are connected in parallel | |
| 1271. |
Organic catalysts differ from the inorganic catalyst in the sense that the former is |
| A. | Active at cryogenic temperatures only |
| B. | Prohibitively costly |
| C. | Proteinous in nature |
| D. | Active at very high temperature only |
| Answer» D. Active at very high temperature only | |
| 1272. |
The optimum performance for reactors operating in parallel is obtained when the feed stream is distributed in such a way, that the |
| A. | Space time for each parallel line is same |
| B. | Space time for parallel lines is different |
| C. | Larger reactors have more space time compared to smaller ones |
| D. | None of these |
| Answer» B. Space time for parallel lines is different | |
| 1273. |
For the gaseous reaction 2A → B, where the feed consists of 50 mole % A and 50 mole % inerts, the expansion factor is |
| A. | 1 |
| B. | -0.5 |
| C. | -0.25 |
| D. | 0 |
| Answer» D. 0 | |
| 1274. |
The rate at which a chemical substance reacts is proportional to its |
| A. | Active mass |
| B. | Equivalent weight |
| C. | Molecular weight |
| D. | None of these |
| Answer» B. Equivalent weight | |
| 1275. |
Higher free energy of activation of a chemical reaction (at a given temperature) implies |
| A. | Slower rate of reaction |
| B. | Higher rate of reaction |
| C. | Higher equilibrium conversion |
| D. | Both (B) and (C) |
| Answer» B. Higher rate of reaction | |
| 1276. |
For any reaction, we may write conversion as a function of |
| A. | Time |
| B. | Temperature |
| C. | Concentration |
| D. | All (A), (B) & (C) |
| Answer» E. | |
| 1277. |
When a high liquid hold up is required in a reactor for gas liquid reaction, use __________ column |
| A. | Packed |
| B. | Spray |
| C. | Tray |
| D. | Bubble |
| Answer» E. | |
| 1278. |
As the chemical reaction proceeds, the rate of reaction |
| A. | Increases |
| B. | Decreases |
| C. | Remain same |
| D. | May increase or decrease depending on the type of reaction |
| Answer» C. Remain same | |
| 1279. |
Helium-mercury method is used for the measurement of the __________ of the catalyst. |
| A. | Surface area |
| B. | Porosity |
| C. | Pore volume |
| D. | Both (B) & (C) |
| Answer» E. | |
| 1280. |
Integral method for analysing the kinetic data is used |
| A. | When the data are scattered |
| B. | For testing specific mechanisms with simple rate expressions |
| C. | Both (A) and (B) |
| D. | None of these |
| Answer» D. None of these | |
| 1281. |
With increase in the space time of an irreversible isothermal reaction being carried out in a P.F. reactor, the conversion will |
| A. | Increase |
| B. | Decrease |
| C. | Remain same |
| D. | Data in insufficient; cant be predicted |
| Answer» B. Decrease | |
| 1282. |
A pulse tracer is introduced in an ideal CSTR (with a mean residence time I) at time, t = 0. The time taken for the exit concentration of the tracer to reach half of its initial value will be |
| A. | 2η |
| B. | 0.5η |
| C. | η/0.693 |
| D. | 0.693η |
| Answer» B. 0.5η | |
| 1283. |
If the rate of a chemical reaction becomes slower at a given temperature, then the |
| A. | Initial concentration of the reactants remains constant |
| B. | Free energy of activation is lower |
| C. | Entropy changes |
| D. | Free energy of activation is higher |
| Answer» E. | |
| 1284. |
Inversion of cane sugar is an example of |
| A. | Unimolecular reaction with first order |
| B. | Bimolecular reaction with second order |
| C. | Bimolecular reaction with first order |
| D. | Unimolecular reaction with second order |
| Answer» D. Unimolecular reaction with second order | |
| 1285. |
The energy of activation of a chemical reaction: |
| A. | Is same as heat of reaction at constant pressure |
| B. | Is the minimum energy which the molecules must have before the reaction can take place |
| C. | Varies as fifth power of the temperature |
| D. | Both (B) and (C) |
| Answer» C. Varies as fifth power of the temperature | |
| 1286. |
Which of the following does not produce a change in the value of rate constant of a reaction? |
| A. | Pressure |
| B. | Temperature |
| C. | Concentration and catalyst |
| D. | None of these |
| Answer» D. None of these | |
| 1287. |
For identical flow rate, feed composition and for elementary first order reactions, 'N' equal sized mixed reactors in series with a total volume 'V' gives the same conversion as a single plug flow reactor of volume 'V' for constant density systems. This is true, when the value of 'N' is |
| A. | 1 |
| B. | > 1 |
| C. | ∞ |
| D. | ≥ 1 |
| Answer» D. ≥ 1 | |
| 1288. |
If pore diffusion is the controlling step in a solid catalysed reaction, the catalyst |
| A. | Porosity is very important |
| B. | Porosity is of less importance |
| C. | Internal surface area is utilised efficiently |
| D. | None of these |
| Answer» C. Internal surface area is utilised efficiently | |
| 1289. |
Pick out the correct statement |
| A. | A catalyst does not change AH of the reaction |
| B. | A catalyst changes the equilibrium point |
| C. | Law of mass action was suggested by Le-Chatelier |
| D. | The difference between the energy of reactants and that of the products is the activation energy |
| Answer» B. A catalyst changes the equilibrium point | |
| 1290. |
With the same reaction time, initial concentration and feed rate, the reaction 2A → B is carried out separately in CSTR and P.F. reactor of equal volumes. The conversion will be |
| A. | Higher in P.F. reactor |
| B. | Higher in CSTR |
| C. | Same in both the reactors |
| D. | Data insufficient; cant be predicted |
| Answer» B. Higher in CSTR | |
| 1291. |
For series reaction, the relative yield |
| A. | Is always greater for plug-flow reactor than for the single CSTR of the same volume |
| B. | Statement in (A) is wrong |
| C. | Decreases with increasing conversion |
| D. | Both (A) and (C) hold good |
| Answer» E. | |
| 1292. |
Usually equal to the residence time |
| A. | Usually equal to the residence time |
| B. | The reciprocal of the space velocity |
| C. | A measure of its capacity |
| D. | Both (A) and (B) |
| Answer» E. | |
| 1293. |
The dispersion number of perfect mixed flow is |
| A. | 0 |
| B. | > 150 |
| C. | ∞ |
| D. | < 2100 |
| Answer» D. < 2100 | |
| 1294. |
The rate of reaction does not decrease appreciably as the reaction proceeds in case of __________ reactions. |
| A. | Autocatalytic |
| B. | Exothermic |
| C. | Endothermic |
| D. | Autothermal |
| Answer» B. Exothermic | |
| 1295. |
In autocatalytic reactions |
| A. | One of the reactants acts as a catalyst |
| B. | One of the products acts as a catalyst |
| C. | Catalysts have very high selectivity |
| D. | No catalyst is used |
| Answer» C. Catalysts have very high selectivity | |
| 1296. |
The order of a chemical reaction is |
| A. | An experimentally determined quantity |
| B. | Always equal to the total stoichiometric number of reactants |
| C. | Never fractional |
| D. | None of these |
| Answer» B. Always equal to the total stoichiometric number of reactants | |
| 1297. |
The rate of a homogeneous reaction is a function of |
| A. | Temperature and pressure only |
| B. | Temperature and composition only |
| C. | Pressure and composition only |
| D. | All temperature, pressure and composition |
| Answer» E. | |
| 1298. |
The reaction rate almost gets doubled for 10°C rise in temperature. This is due to the fact that the |
| A. | Increased temperature reduces the activation energy |
| B. | Fraction of molecules having threshold energy increases |
| C. | Collision frequency increases |
| D. | Value of threshold energy decreases |
| Answer» C. Collision frequency increases | |
| 1299. |
The rate of the reaction, X → Y, quadruples when the concentration of 'X' is doubled. The rate expression for the reaction is, r = K Cx n , the value of 'n' in this case will be |
| A. | 0 |
| B. | 1 |
| C. | 2 |
| D. | 3 |
| Answer» D. 3 | |
| 1300. |
In an ideal P.F.R. at steady state conditions |
| A. | The composition of reactants remains constant along a flow path |
| B. | The conversion of the reactant varies from point to point along a flow path |
| C. | There is no lateral mixing of fluid |
| D. | There may be diffusion along the flow path |
| Answer» C. There is no lateral mixing of fluid | |