Chemical Reaction Engineering Mid - I, September - 2014

1.The important factor in comparing design of single reaction is __________
  • Reactor size
  • Reactor height
  • Temperature
  • Pressure
Answer: A
2.In a semi batch reactor
  • Velocity of a reaction can be controlled
  • Maximum conversion can be controlled
  • Both the reactant flow counter-currently
  • Residence time is constant
Answer: B
3.A batch reactor is characterized by
  • Constant Residence Time
  • Variation in extent of reaction and properties of the reaction mixture with time
  • Variation in reactor volume
  • Very low conversion
Answer: B
4.A high reactant concentration favours the reaction of __________order.
  • high
  • low
  • zero
  • 1/2
Answer: A
5.For a zero order reaction concentration of product increases with
  • Increase in reaction time
  • Increase in initial concentration
  • Increase in total pressure
  • Decrease in total pressure
Answer: A
6.The dimensionless reaction rate group for first order reaction is defined as __________
  • k
  • kCA0
  • kρCA0
  • kμCA0
Answer: A
7.For 5 liter PFR with 1st order reaction with 1lit/min flow and 2 mole/liter inlet concentration, If the exit concentration is 0.5mole/lit then the rate constant is
  • 0.06
  • 0.28
  • 0.42
  • 0.64
Answer: D
8.Plug-flow reactor is characterized by
  • High capacity
  • Presence of axial mixing
  • Presence of lateral mixing
  • Constant composition and temperature
Answer: B
9.Half-life period for a 1st order reaction compared to initial concentration of reaction
  • Directly proportional
  • Inversely proportional
  • Independent
  • None of the above
Answer: A
10.In the presence of a catalyst, the equilibrium constant of a chemical reaction
  • Increases
  • Decreases
  • Uncertain
  • Remains same
Answer: A
11.The reaction in which the rate equation corresponds to stoichiometric equation is called ____________________
Answer: Elementary reaction
12.The unit of rate of reaction for 1st order reaction is ____________________
Answer: Time-1
13.If the heat of reaction is negative, it is an ____________________ reaction.
Answer: Exothermic
14.The equilibrium constant relation from thermodynamics is ____________________
Answer: Ln k = -G/RT
15.When large number of CSTRs are connected in series, it is equivalent to ____________________ reactor.
Answer: Plug flow
16.If Ethyl formate (EF) is to be produced from ethanol (EtOH) and formic acid (FA) in PFR & is 2nd order with respect to formic acid, then its rate expression can be written as ____________________
Answer: kCFA2
17.The units of rate constant (k) for second order reaction is ____________________
Answer: Lit/mol min
18.In the reaction N2 + 3H2 -> 2NH3, when 15moles of N2 and 90moles of H2 reacted to get 10 moles of NH3, then the percentage conversion is ____________________
Answer: 75%
19.The half-life of a 1st order reaction is 30 seconds. Then the rate constant is ____________________
Answer: 2
20.According to Arrhenius equation, temperature (T) dependency for an elementary reaction with rate constant k can be expressed as k = ____________________
Answer: k0*EXP(-E/RT)