GATE CH kind:question PYQs & Answers — Page 26

Questions 251–260 of 650. Imported answers require independent review unless marked reviewed.

Topic practice 650 questionsPage 26 of 65

Partially saturated air at 1 bar and 50 °C is contacted with water in an adiabatic saturator. The air is cooled and humidified to saturation, and exits at 25 °C with an absolute humidity of 0.02 kg water per kg dry air. Use latent heat of vaporization of water as 2450 kJ·kg

, and average specific heat capacity for dry air and water, respectively as 1.0 kJ·kg

·K

and 4.18 kJ·kg

·K

. If the absolute humidity of air entering the adiabatic saturator is

kg water per kg dry air, the value of

is __________ (rounded off to two decimal places).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Distillation of a non-reactive binary mixture with components

and

is carried out in a batch still as shown in the figure below. The initial charge of the mixture in the still is 1 kmol. The initial and final amounts of

in the still are 0.1 kmol and 0.01 kmol, respectively. Use a constant relative volatility of 4.5. The mole fraction of

remaining in the vessel is ______ (rounded off to three decimal places).

Diagram for Chemical Engineering question 57

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Fresh catalyst is loaded into a reactor before the start of the following catalytic reaction:

The catalyst gets deactivated over time. The instantaneous activity

, at time

, is defined as the ratio of the rate of the reaction

(mol·(g cat)

·hr

) to the rate of reaction with fresh catalyst. Controlled experimental measurements led to an empirical correlation

where

is in hours. The activity of the catalyst at

hr is ______ (rounded off to one decimal place).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

A unimolecular, irreversible liquid-phase reaction

was carried out in an ideal batch reactor at temperature

. The rate of the reaction (

) measured at different conversions

is given in the table below. This reaction is also carried out in an ideal continuous stirred tank reactor (CSTR) at the same temperature

with a feed concentration of 1 mol m

, under steady-state conditions. For a conversion of 0.8, the space time (in s) of the CSTR is ______ (in integer).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

An irreversible liquid-phase second-order reaction

with rate constant

liter·mol

·min

, is carried out in an isothermal non-ideal reactor. A tracer experiment conducted on this reactor resulted in a residence time distribution (

-curve) as shown in the figure below. The areas of the rectangles (i), (ii) and (iii) are equal. Pure

at a concentration of 1.5 mol·liter

is fed to the reactor. The segregated model mimics the nonideality of the reactor. The percentage conversion of

at the exit of the reactor is _____ (rounded off to the nearest integer).

Diagram for Chemical Engineering question 60

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

The outlet concentration

of a plug flow reactor (PFR) is controlled by manipulating the inlet concentration

. The following transfer function describes the dynamics of this PFR.

In the above equation,

min

and

min

. The measurement and valve transfer functions are both equal to 1. The ultimate gain, defined as the proportional controller gain that produces sustained oscillations, for this system is _____ (rounded off to one decimal place).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

The transfer function of a measuring instrument is

At time

, a step change of +1 unit is introduced in the input of this instrument. The time taken by the instrument to show an increase of 1 unit in its output is _____ (rounded off to two decimal places).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

A design engineer needs to purchase a membrane module (M) for a plant. Details about the two available options, M1 and M2, are given in the table below. The overall plant has an expected life of 7 years. If the interest rate is 8% per annum, compounded annually, the difference in the net present value (NPV) of these two options, in lakhs of rupees, is _____ (rounded off to one decimal place).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

The purchase cost of a new distillation column is Rs. 10 lakhs with an installation factor of 5.8. The cost of the capital is to be annualized over a period of 6 years at a fixed rate of interest of 5 % per annum, compounded annually. The annual cost (in lakhs of rupees) of the installed capital is ______ (rounded off to one decimal place).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

Pumps

and

are being considered for purchase in a chemical plant. Cost details for these two pumps are given in the table below. The interest rate is 10 % per annum, compounded annually. For both the pumps to have the same capitalized cost, the salvage value (in Rs.) of pump B should be _____ (rounded off to the nearest integer).

You can attempt this question now. Sign in to view the answer key, explanations and discussion.Log in to check answer

GATE CH kind:question PYQs

Question 56

Question 57

Question 58

Question 59

Question 60

Question 61

Question 62

Question 63

Question 64

Question 65