17801. A chemical reaction is of zero order, when the reaction rate is (where, CA = concentration of reactant)
17802. Second order consecutive irreversible reactions were carried out in a constant volume isothermal batch reactor with different initial feed compositions. Reactor temperature was same in all the cases. In experiments where the ratio of concentration of B to that of A in the initial feed was less than 0.5, the concentration of B increased first, reached a maximum and then declined with time. However, for all experiments where this concentration ratio was 0.5 or above, concentration of B decreased monotonically with time right from the beginning. What is the ratio of the two rate constants (k1/k2)?
17803. What is a smart card with embedded chip,having multiple payment option?
17804. There is no correspondence between stoichiometry and the rate equation in case of a/an __________ reaction.
17805. A spherical porous catalyst particle of radius R is subjected to reactant A which reacts to form B by a zero order surface reaction A B. Film mass transfer resistance is negligible and pore diffusion of A is rate controlling. The effectiveness factor of the catalyst is reported as 7/8. Which of the following statement is true?
17806. Which of the following is used for calcination of limestone and dolomite in industrial practice ?
17807. An imbalanced chemical reaction equation is against the law of
17808. For the chemical reaction P Q, it is found that the rate of reaction doubles as the concentration of 'P' is doubled. If the reaction rate is proportional to Cpn, then what is the value of 'n' for this chemical reaction ?
17809. Which of the following is a characteristic of an ideal plug flow reactor ?
17810. Velocity of a reaction depends upon the
17811. Threshold energy in a reaction is equal to the
17812. An isothermal aqueous phase reversible reaction, P R, is to be carried out in a mixed flow reactor. The reaction rate in k.mole/m3 .h is given by, r = 0.5CP - 0.125CR. A stream containing only P enters the reactor. The residence time required (in hours) for 40% conversion of P is
17813. Design of heterogeous catalytic reactor involves consideration of __________ steps.
17814. A consecutive reaction, , is characterised by
17815. What is the unit of the rate constant in a chemical reaction in which 10% of the reactant decomposes in one hour, 20% in two hours, 30% in three hours and so on ?
17816. For a fluidised bed reactor, the most suitable/relevant model is a __________ model.
17817. Shares offered to the existing shareholders free of cost
17818. In a reaction, the threshold energy is equal to (where, A = activation energy N = normal energy of reactants)
17819. Thermodynamic equilibrium constant in a system is affected by
17820. The most suitable reactor for carrying out an auto-thermal reaction is a
17821. Which of the following chemical reactions will be favoured by low pressure ?
17822. A catalyst in a chemical reaction
17823. Slurry reactors are characterised by the
17824. Limiting reactant in a chemical reaction decides the
17825. Consider the 'n' th order irreversible liquid phase reaction A B. Which one of the following plots involving half life of the reaction (t1/2) and the initial reactant concentration (CA0) gives a straight line plot ?
17826. The rate of forward reaction, at chemical equilibrium is____the rate of backward reaction.
17827. Pick the WRONG design guideline for a reactor in which the reactions, A R (desired) and A S (undesired) are to take place. The ratio of the reaction rates is .
17828. With increase in temperature, the equilibrium __________ rises in case of endothermic reaction.
17829. In case of a consecutive unimolecular type first order reaction , the concentration of component __________ increases continuously with time.
17830. Enzymes (a protein) are catalysts found in organisms. Its efficiency of catalysing a reaction is due to its capacity to lower the activation energy of the reaction. The enzyme ptyalin used for food digestion is present in
17831. Considering the endotheomic dissociation of CaCO3 in a closed vessel (CaCO3 CaO + CO2), the pressure of CO2 increases, if
17832. The exit age distribution of fluid leaving a vessel is used to know the
17833. From Arhenius law, a plot of loge K versus 1/T gives a straight line with a slope of (-E/R). The unit of E/R is
17834. In the converter of the contact process for the manufacture of H2SO4 the equilibrium conversion of SO2 __________ (A) __________ with increase in temperature and __________ (B) __________ with increase in the mole ratio of SO2 to air.
17835. For the irreversible elementary first order reaction in parallel viz. , a plot of Cy Vs. Cz will give a straight line having a slope of
17836. The time needed to achieve the same fractional conversion for particles of different sizes (d) when chemical reaction controls, is proportional to
17837. A balanced chemical reaction equation conforms to the law of
17838. An exothermic reaction takes place in an adiabatic reactor. The product temperature __________ reactor feed temperature.
17839. Reverse reaction in a chemical equilibrium is favoured by the
17840. The equilibrium constant for the reversible reaction, , is affected by the
17841. Sum of the powers of the concentration terms in the rate equation is called the __________ of the reaction.
17842. During manufacture of H2SO4, the oxidation of SO2 to SO3 by oxygen is an en-dothermic reaction. The yield of SO3 will be maximised, if the
17843. The role of a catalyst in a chemical reaction is to change the
17844. The vessel dispersion number (D/μL) for plug flow is
17845. Molecularity of a reaction
17846. BET apparatus is used to determine the
17847. Carrier in a catalyst increases its
17848. When the reaction is dominated by in-traparticle diffusion, the apparent order of reaction (nD) as measured is related to the true order (n) as
17849. When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value.
17850. An isothermal irreversible reaction is being carried out in an ideal tubular flow reactor. The conversion in this case will __________ with decrease in space time.