JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B. Tech II Year CHEMICAL PROCESS CALCULATIONS Previous Question Paper (August/ September - 2022 - R18)

Define one gram-moles of a substance. Give examples.

Explain the relation between mass and volume for gaseous substances.

20 gm of caustic soda (NaOH) is dissolved in water to prepare 500 ml of solution. Find the normality and molarity of solution.

Define Baumé scale and API gravity scale. Mention the applications of these scales.

At 298 K, the solubility of methyl bromide (CH₃Br) in methanol (CH₃OH) is 44 kg per 100 kg. Calculate the weight fraction and mole fraction of methanol in the saturated solution. Atomic mass data’s are: Br = 79.9, C = 12, H = 1 and O = 16.

A gas mixture contains 0.274 kmol of HCl, 0.337 kmol of N₂ and 0.089 kmol of O₂. Calculate the average molecular weight of gas. Molecular mass of HCl = 36.5 g/mol. Atomic mass of nitrogen is N = 14.

Mention the physical meaning of critical temperature and critical pressure for a substance.

The dry bulb temperature and dew point of ambient air were found to be 302 K and 291 K respectively. Barometer reads 100 kPa. Calculate: the absolute molal humidity, the absolute humidity, the % relative humidity, the % saturation, the humid heat and the humid volume. Data are: vapor pressure of water at 291 K = 2.0624 kPa and vapor pressure of water at 302 K = 4.004 kPa.

Discuss the effect of temperature on vapor pressure according to Clapeyron equation.

Explain the following:

i) recycle, bypass & purge

ii) Conversion & yield

The waste acid from a nitrating process contains 30% H₂SO₄, 35% HNO₃ and 35% H₂O by weight. The acid is to be concentrated to contain 39% H₂SO₄ and 42% HNO₃ by addition of concentrated sulfuric acid containing 98% H₂SO₄ and concentrated nitric acid containing 72% HNO₃ (by weight). Calculate the quantities of three acids to be mixed to get 1000 kg of desired mixed acid.

What is tie-substance? Mention the uses of tie-substance in process calculations.

What are the two methods employed for expressing the yields of a recycling operation?

A two – stage dryer system handles 1000 kg/day of wet solids. A sample of wet solids containing 50% solids and 50% water are fed to the first dryer. From the first dryer, the product that comes out has 20% moisture. This is admitted to the second dryer from which the product coming out has 2% moisture. Calculate the % of original water that is removed in each dryer and final weight of the product.

Explain the importance of by – passing streams and purge streams in process industries.

Define extent of reaction and stoichiometric coefficient in a chemical reaction.

Write the energy balance equation for steady flow process and for a non – flow process without chemical reactions. Explain the terms in the equation.

A stream of nitrogen flowing at a rate of 100 kmol/h is heated from 303 K to 373 K. Calculate the heat that must be transferred. Heat capacity for nitrogen is CP = 29.5909 + 5.141x10^-3T - 11.1829 x 10^-6T² + 4.968 x 10^-9T³.

State and explain: Kopp’s rule and Trouton’s rule.

Explain the following terms in combustion: Gross Calorific value (GCV), theoretical air, theoretical oxygen and percent excess air.

The Orsat analysis of the flue gases from a boiler house chimney by volume is given as follows: CO₂ = 11.4%, O₂ = 4.2% and N₂ = 84.4%. Assuming that complete combustion takes place, calculate the % excess air used.