adspace


Topic :: Reaction





Reaction Interview Questions
Questions Answers Views Company eMail

CHEMICAL ENERGY BALANCE - EXAMPLE 11.1 : Please match the term A - E with the stated definition i - v. Terms : A. Yield. B. Selectivity. C. Relative saturation. D. Molal saturation. E. Absolute saturation. Definitions : i. (moles of desired product formed) / (moles that would have been formed if there were no side reactions and the limiting reactant has reacted completely); ii. (moles of desired product formed) / (moles of undesired product formed); iii. (relative humidity 40 % means partial pressure of water vapour equals 4 / 10 of the vapour pressure of water at the system temperature); iv. (moles of vapour) / (moles of vapour dry gas); v. (mass of vapour) / (mass of dry gas).

1 2418

REACTION ENGINEERING - EXAMPLE 13.1 : In a furnace, 2 chemical reactions are happening - 1 mole of solid carbon reacts with 1 mole of oxygen gas to generate 1 mole of carbon dioxide gas; 1 mole of solid carbon reacts with 0.5 mole of oxygen gas to generate 1 mole of carbon monoxide gas. In a given process, 100 kmol of carbon is burned in a furnace. (a) Calculate the theoretical oxygen gas needed by assuming that all the carbon is burned completely to carbon dioxide gas. (b) Calculate the theoretical air needed by assuming that all the carbon is burned completely to carbon dioxide gas and there is only 21 % of oxygen gas. (c) Determine the amount of air required (in kmol) if 50 % excess oxygen gas must be satisfied for (a) and (b). (d) It has latter been found that 20 % of the carbon undergoes incomplete combustion resulting to carbon monoxide gas production. The rest of the carbon undergoes complete combustion. Calculate the total oxygen gas required stoichiometrically based on the actual process.

1 2848

REACTION ENGINEERING - EXAMPLE 13.2 : A batch reactor is designed for the system of the irreversible, elementary liquid-phase hydration of butylene oxide that produces butylene glycol. At the reaction temperature T = 323 K, the reaction rate constant is k = 0.00083 L / (mol - min). The initial concentration of butylene oxide is 0.25 mol / L = Ca. The reaction is conducted using water as the solvent, so that water is in large excess. (a) Let the molecular weight of water is 18 g / mol and the mass of 1 kg in 1 L of water, calculate the molar density of water, Cb in the unit of mol / L. (b) Determine the final conversion, X of butylene oxide in the batch reactor after t = 45 min of reaction time. Use the formula X = 1 - 1 / exp [ kt (Cb) ] derived from material balance. (c) Find the equation of t as a function of X.

1 2509

REACTION ENGINEERING - EXAMPLE 13.3 : The half-life for first order reaction could be described in the differential equation dC / dt = -kC where k is a constant, C is concentration and t is time. (a) Find the equation of C as a function of t. (b) Find the half life for such reaction or the time required to reduce 50 % of the initial concentration, where k = 0.139 per minute. (c) When the initial concentration Co is 16 mol / cubic metre, how long does the reaction required to achieve the final concentration of 1 mol / cubic metre?

1 2300

FOOD ENGINEERING - QUESTION 23.3 : (a) In the measurement of the browning (optical density) of fruit juice at 10 day interval, the following pairs of data are obtained with time t in days and browning or optical density (OD) : t = 0, OD = 0.05; t = 10, OD = 0.071; t = 20, OD = 0.089; t = 30, OD = 0.11; t = 40, OD = 0.128; t = 50, OD = 0.149; t = 60, OD = 0.17. (i) By using Excel or other programs, determine if such browning reaction can be characterised by pseudo zero order kinetics, with strong correlations between the data pairs of t and OD. (ii) When OD = 0.24, the shelf life T of such juice is expired. Calculate the value of T. (b) Let food cost percentage = ( food cost / food sales ) x 100. If total food cost of bread and butter are $25, food cost percentage of bread is 50 % and for butter is 50 %, find the total food sales of bread and butter.

1 2349

If you came across your colleagues engaging in idle gossip, what would be your reaction?

Amazon,

1 1315

What is the usage of draft tube in reaction turbine ?

John Deere,

1 1224

Which of the following is produced during allergic reactions ? a) Heparin b) Histamine c) Seratonin d) Selastamine

1 1661

Your project involves the research and development of a new food additive. You’re ready to release the product to your customer when you discover that a minor reaction might occur in people with certain conditions. The reactions to date have been very minor, and no known long-lasting side effects have been noted. As project manager you should: A. Do nothing because the reactions are so minor that very few people will be affected. B. Inform the customer that you've discovered this condition and tell them you'll research it further to determine the impacts. C. Inform your customer that there is no problem with the additive release the product to them. D. Tell the customer you'll correct the reaction problems in the next batch but you'll release the first batch of product to them now to begin using.

1 1227

How does facilitated diffusion present similarities with enzymatic chemical reactions?

1 1066

How can you determine the reaction, taking place at constant pressure delta (h)?

1 1224

How do you define the molecularity of a reaction?

1 1176

What is the reaction-taking place when H2 receptor binds to mast cells and basophils?

1 693

How many types of hypersensitive reactions are there?

1 677

Give the example for electrophilic substitution reaction?

1 1282




Un-Answered Questions { Reaction }

1- XC and the RC time constant are both measures of the reaction of C to a change in ____? 2-The power factor is a numerical ratio with a value between 0 and 1 equal to the ______________ of the phase angle. 3-When V and I are out of phase because of reactance, the product of V times I is called ______________ power 4-For _____________ inductors, the branch currents can be added algebraically. 5- The ______________ power in watts can be calculated as I^2R 6-Calculate XL with L = 30mH and f = 1kHz ( I have Xl=2piFL 2*3.141592653*1kHz*30mH =188 ohms Please check) 7-A parallel RL circuit has the values, R = 5kohms, XL = 5kohms. A voltage source of Vt = 10Vrms is connected in parallel to R and L. Determine the total current, It delivered by the voltage source Vt. 8-A series RC circuit has R = 1Mohm and C = 1microF. How long would it take for the capacitor to fully discharge if it is initially fully charged? 9-A circuit has real power = 300W and an apparent power of 500VA. Determine the power factor and phase angle. 10-The time constant for an LR series circuit is T = 0.1s and R = 10ohms. Calculate the inductance L.

3458