Process Calculations GATE-1990
Fill in the blanks (Questions 1 & 2):
Q 1: A mixture of ethyl acetate vapor and air has a relative saturation of 50 % at 300 C and a total pressure of 100 kN/m2. If the vapor pressure of ethyl acetate at 300 C is 16 kN/m2. (a) The percentage of air ____________. (b) The molal saturation is ____________.
Q 2: The following data on heats of combustion at 25 ℃ are given:
Compound | Heat of Combustion at 25 ℃ |
---|---|
n-Heptane C7H10 (g) | – 4850 kJ/mol |
Ethyl Alcohol C2H5OH (g) | -1410 kJ/mol |
The heat of formation of CO2 (g) and H2O (l) are -380 kJ/mol and -280 kJ/mol respectively. (a) The heat of formation of gaseous n-Heptane at 250 C is _________. (b) The heat of the formation of gaseous Ethyl Alcohol at 250 C is _______.
Q 2: Pure propane (C3H8) is burnt in excess of air to give the following analysis of combustion products in the volume present: CO2 = 5.0, CO = 3.5, H2O = 11.4, O2 = 7.0 and N2 = 73.1. Calculate the percentage of excess air used.
Q 3: The process flow diagram is shown in the figure for the reaction A to B. The fresh feed of A contains 0.5 % inert by volume, and 80 % conversion per pass of A fed to the reactor is obtained. The concentration of inert going into the reactor (after mixing with the recycle stream) must be held at 2 % by volume. All streams are ideal gases and the process is at a steady state. How many moles must be recycled per mole of total feed (mixed feed) to the reactor?