GATE 2021 CH – Previous Year Questions with Solutions
All 65 questions of GATE 2021 CH with answers and explanations. Read each question, then practise it by topic or as a full paper.
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- Question 1 – The ratio of boys to girls in a class is 7 to 3. Among the options below, an acceptable value for the total number of students in the class is:
- Question 2 – A polygon is convex if, for every pair of points, P and Q belonging to the polygon, the line segment PQ lies completely inside or on the polygon.…
- Question 3 – Consider the following sentences: (i) Everybody in the class is prepared for the exam. (ii) Babu invited Danish to his home because he enjoys playing…
- Question 4 – A circular sheet of paper is folded along the lines in the directions shown. The paper, after being punched in the final folded state as shown and…
- Question 5 – is to surgery as writer is to . Which one of the following options maintains a similar logical relation in the above sentence?
- Question 6 – We have 2 rectangular sheets of paper, M and N, of dimensions 6 cm × 1 cm each. Sheet M is rolled to form an open cylinder by bringing the short edges…
- Question 7 – Details of prices of two items P and Q are presented in the table. The ratio of cost of item P to cost of item Q is 3:4. Discount is calculated as the…
- Question 8 – There are five bags each containing identical sets of ten distinct chocolates. One chocolate is picked from each bag. The probability that at least…
- Question 9 – Given below are two statements 1 and 2, and two conclusions I and II. Statement 1: All bacteria are microorganisms. Statement 2: All pathogens are…
- Question 10 – Some people suggest anti-obesity measures (AOM) such as displaying calorie information in restaurant menus. Such measures sidestep addressing the core…
- Question 11 – An ordinary differential equation (ODE), dy/dx=2y, with an initial condition y(0)=1, has the analytical solution y=e2x. Using Runge-Kutta second order…
- Question 12 – The function (x) is approximated using Taylor series around x=0 as (x)1+ax+bx2+cx3+dx4. The values of a,b,c and d are
- Question 13 – The heat of combustion of methane, carbon monoxide and hydrogen are P,Q and R respectively. For the reaction below, CH 4+H 2O CO+3H 2, the heat of…
- Question 14 – A batch settling experiment is performed in a long column using a dilute dispersion containing equal number of particles of type A and type B in water…
- Question 15 – A three-dimensional velocity field is given by V=5x2y\, i+Cy\, j-10xyz\, k, where i, j, k are the unit vectors in x,y,z directions, respectively,…
- Question 16 – Heat transfer coefficient for a vapor condensing as a film on a vertical surface is given by
- Question 17 – In a double-pipe heat exchanger of 10 m length, a hot fluid flows in the annulus and a cold fluid flows in the inner pipe. The temperature profiles of…
- Question 18 – For a shell-and-tube heat exchanger, the clean overall heat transfer coefficient is calculated as 250\ W\,m-2\,K-1 for a specific process condition.…
- Question 19 – In reverse osmosis, the hydraulic pressure and osmotic pressure at the feed side of the membrane are P 1 and 1, respectively. The corresponding values…
- Question 20 – Ethylene adsorbs on the vacant active sites V of a transition metal catalyst according to the mechanism C 2H 4+2V C 2H 4 adsorbed on two sites. If N…
- Question 21 – Which of the following is NOT a standard to transmit measurement and control signals?
- Question 22 – A feedforward controller can be used only if
- Question 23 – Turnover ratio is defined as
- Question 24 – A principal amount is charged a nominal annual interest rate of 10%. If the interest rate is compounded continuously, the final amount at the end of…
- Question 25 – Match the common name of chemicals in Group – 1 with their chemical formulae in Group – 2. Group – 1 Group – 2 --- --- P: Gypsum I: Ca(H 2PO 4) 2 Q:…
- Question 26 – For the function f(x)=cases-x,&x<0\2,&x0cases, the CORRECT statement(s) is/are
- Question 27 – Feed solution F is contacted with solvent B in an extraction process. Carrier liquid in the feed is A and the solute is C. The ternary diagram…
- Question 28 – The inherent characteristics of three control valves P, Q and R are shown in the figure. The CORRECT option(s) is/are
- Question 29 – A source placed at the origin of a circular sample holder (radius r=1 m) emits particles uniformly in all directions. A detector of length l=1 cm has…
- Question 30 – A,B,C and D are vectors of length 4: A=[a 1\ a 2\ a 3\ a 4], B=[b 1\ b 2\ b 3\ b 4], C=[c 1\ c 2\ c 3\ c 4], D=[d 1\ d 2\ d 3\ d 4]. It is known that…
- Question 31 – The van der Waals equation of state is given by P r=8T r3v r-1-3v r2, where P r,T r and v r represent reduced pressure, reduced temperature and…
- Question 32 – Consider a steady flow of an incompressible, Newtonian fluid through a smooth circular pipe. Let laminar and turbulent denote the kinetic energy…
- Question 33 – The molar heat capacity at constant pressure C p (in J\,mol-1\,K-1) for n-pentane as a function of temperature (T in K) is given by C…
- Question 34 – The following homogeneous liquid phase reactions are at equilibrium. The values of rate constants are given by: k 1=0.1\ s-1, k -1=0.2\ s-1, k 2=1\…
- Question 35 – A company invests in a recovery unit to separate valuable metals from effluent streams. The total initial capital investment of this unit is Rs. 10…
- Question 36 – Let A be a square matrix of size n n (n>1). The elements of A=\a ij\ are given by a ij=casesi j,&i j\\0,&i<jcases. The determinant of A is
- Question 37 – Consider a fluid confined between two horizontal parallel plates and subjected to shear flow. In the first experiment, the plates are separated by a…
- Question 38 – Water of density 1000\ kg\,m-3 flows in a horizontal pipe of 10 cm diameter at an average velocity of 0.5\ m\,s-1. The plot shows the pressure…
- Question 39 – In a solvent regeneration process, a gas is used to strip a solute from a liquid in a countercurrent packed tower operating under isothermal…
- Question 40 – Which of these symbols can be found in piping and instrumentation diagrams?
- Question 41 – It is required to control the volume of the contents in the jacketed reactor shown in the figure. Which one of the following schemes can be used for…
- Question 42 – Which of the following is NOT a necessary condition for a process under closed-loop control to be stable?
- Question 43 – Match the reaction in Group – 1 with the reaction type in Group – 2. Group – 1 Group – 2 --- --- P: Methylcyclohexane → Toluene + 3 H 2 I:…
- Question 44 – To solve an algebraic equation f(x)=0, an iterative scheme of the type x n+1=g(x n) is proposed, where g(x)=x-f(x)f(x). At the solution x=s, g(s)=0…
- Question 45 – The probability distribution function of a random variable X is shown in the figure. From this distribution, random samples with sample size n=68 are…
- Question 46 – For the ordinary differential equation d3ydt3+6d2ydt2+11dydt+6y=1, with initial conditions y(0)=y(0)=y(0)=y(0)=0, the value of ty(t) is (round off to…
- Question 47 – Formaldehyde is produced by the oxidation of methane in a reactor. The following two parallel reactions occur: CH 4+O 2 HCHO+H 2O and CH 4+2O 2 CO…
- Question 48 – The combustion of carbon monoxide is carried out in a closed, rigid and insulated vessel. 1 mol of CO, 0.5 mol of O 2 and 2 mol of N 2 are taken…
- Question 49 – A gaseous mixture at 1 bar and 300 K consists of 20 mol% CO 2 and 80 mol% inert gas. Assume the gases to be ideal. Take R = 8.314 J/(mol K). The…
- Question 50 – A binary liquid mixture consists of two species 1 and 2. Let and x represent the activity coefficient and the mole fraction of the species,…
- Question 51 – Consider a tank filled with 3 immiscible liquids A, B and C at static equilibrium, as shown in the figure. At 2 cm below the liquid A–liquid B…
- Question 52 – Seawater is passed through a column containing a bed of resin beads. Density of seawater = 1025\ kg\,m-3; density of resin beads = 1330\ kg\,m-3;…
- Question 53 – A straight fin of uniform circular cross section and adiabatic tip has an aspect ratio (length/diameter) of 4. If the Biot number (based on radius of…
- Question 54 – A double-effect evaporator is used to concentrate a solution. Steam is sent to the first effect at 110 °C and the boiling point of the solution in the…
- Question 55 – Consider a solid slab of thickness 2L and uniform cross section A. The volumetric rate of heat generation within the slab is q (W/m³). The slab loses…
- Question 56 – A distillation column handling a binary mixture of A and B is operating at total reflux. It has two ideal stages including the reboiler. The mole…
- Question 57 – In a batch drying experiment, a solid with a critical moisture content of 0.2 kg H₂O/kg dry solid is dried from an initial moisture content of 0.35 kg…
- Question 58 – As shown in the figure, air flows in parallel to a freshly painted solid surface of width 10 m, along the z-direction. The equilibrium vapor…
- Question 59 – The following isothermal autocatalytic reaction, A+B2B, (-r A)=0.1C AC B (mol L⁻¹ s⁻¹), is carried out in an ideal continuous stirred tank reactor…
- Question 60 – Reactant A decomposes to products B and C in the presence of an enzyme in a well-stirred batch reactor. The kinetic rate expression is -r A=0.01C…
- Question 61 – The following homogeneous, irreversible reaction involving ideal gases, A B+C, (-r A)=0.5C A (mol L⁻¹ s⁻¹), is carried out in a steady state ideal…
- Question 62 – A system has a transfer function G(s)=3e-4s12s+1. When a step change of magnitude M is given to the system input, the final value of the system output…
- Question 63 – A process has a transfer function G(s)=Y(s)X(s)=2090000s2+240s+1. Initially the process is at steady state with x(t=0)=0.4 and y(t=0)=100. If a step…
- Question 64 – Operating labor requirements L in the chemical process industry is described in terms of the plant capacity C (kg/day) over a wide range (103–106) by…
- Question 65 – A viscous liquid is pumped through a pipe network in a chemical plant. The annual pumping cost per unit length of pipe is given by C pump=48.13q2/D4.…