Chemical Engineering Gate 2011 Questions with Answer

Ques 53 GATE 2011

A binary feed mixture containing equimolar quantities of components S and T is to be distilled in a fractionating tower at atmospheric pressure. The distillate contains 96 mol % S. The q-line (feed line) intersects the equilibrium line at x′ = 0.46 and y′ = 0.66, where x′ and y′ are mole fractions. Assume that the McCabe–Thiele method is applicable and the relative volatility is constant.
The MINIMUM reflux ratio is

Ques 54 GATE 2011

A binary feed mixture containing equimolar quantities of components S and T is to be distilled in a fractionating tower at atmospheric pressure. The distillate contains 96 mol % S. The q-line (feed line) intersects the equilibrium line at x′ = 0.46 and y′ = 0.66, where x′ and y′ are mole fractions. Assume that the McCabe–Thiele method is applicable and the relative volatility is constant.
The feed is

Ques 55 GATE 2011

Ammonia (component 1) is evaporating from a partially filled bottle into surrounding air (component 2). The liquid level in the bottle and the concentration of ammonia at the top of the bottle are maintained constant. N_i is the molar flux relative to a fixed location in space and J_t is the molar flux with respect to the average molar velocity of the constituent species in the gas phase. Assume that air in the bottle is stagnant. Which ONE of the following is CORRECT?

Ques 56 GATE 2011

An aqueous sodium chloride solution (10 wt%) is fed into a single effect evaporator at a rate of 10000 kg/hr. It is concentrated to a 20 wt% sodium chloride solution. The rate of consumption of steam in the evaporator is 8000 kg/hr. The evaporator capacity (kg/hr) and economy are

Ques 57 GATE 2011

A gas mixture is in contact with a liquid. Component P in the gas mixture is highly soluble in the liquid. Possible concentration profiles during absorption of P are shown in the choices, where
x: mole fraction of P in bulk liquid
y: mole fraction of P in bulk gas
x_i: mole fraction of P at the interface in liquid
y_i: mole fraction of P at the interface in gas
y*: equilibrium gas phase mole fraction corresponding to x_i
The CORRECT profile is

Ques 58 GATE 2011

A batch of 120 kg wet solid has initial moisture content of 0.2 kg water/kg dry solid. The exposed area for drying is 0.05 m²/kg dry solid. The rate of drying follows the curve given below.

Ques 59 GATE 2011

Minimum input required to calculate the 'blank diameter' for a torispherical head is

Ques 60 GATE 2011

Match the pumps in Group I with the corresponding fluids in Group II.
GROUP I
P. Gear pump
Q. Peristaltic pump
GROUP II
I. Highly viscous liquid
II. Aqueous sterile liquid
III. Slurry

Ques 61 GATE 2011

Two systems are available for compressing 6 m³/hr of ambient air to 10 bar. The first one uses a single stage compressor (KI) and the second one uses a multistage compressor with inter-stage cooling (K2). Which ONE of the following statements is INCORRECT?

Ques 62 GATE 2011

In a thin-walled cylindrical vessel of thickness t with inside radius r, the internal gauge pressure is p. The hoop stress and the longitudinal stress in the shell are σ_h σ_l respectively. Which ONE of the following statements is TRUE?

Ques 63 GATE 2011

The particle size distributions of the feed and collected solids (sampled for same duration) for a gas cyclone are given below.

Ques 64 GATE 2011

A process plant has a life of 7 years and its salvage value is 30%. For what MINIMUM fixed-percentage factor will the depreciation amount for the second year, calculated by declining balance method be EQUAL to that calculated by the straight line depreciation method?

Ques 65 GATE 2011

A continuous fractionator system is being designed. The following cost figures are estimated for a reflux ratio of 1.4.