Bissoy.com
Doctors Medicines MCQs Q&A

When pure carbon is burned in air, some of it oxidizes into CO2 and some to CO. The molar ratio of N2 to O2 is 7.18 and the ratio of CO to CO2 is 2.0 in the product gas. What is the percent excess air used? The exit gases contain only N2, O2, CO and CO2.

When pure carbon is burned in air, some of it oxidizes into CO2 and some to CO. The molar ratio of N2 to O2 is 7.18 and the ratio of CO to CO2 is 2.0 in the product gas. What is the percent excess air used? The exit gases contain only N2, O2, CO and CO2. Correct Answer 40 %

The process involves two reactions: R1 = C + O2 = CO2 R2 = C + 1/2 O2 = CO As the product (output) gas composition is specified more clearly, we may use it as starting point. Take N2 in the product as nN2 = Take N2 in the product as, then O2 = 1 mol N2 as an inert gas: input = output = 7.18 mol O2 input with air = 7.18 (21/79) = 1.91 mol Total O2 consumption = 1.91-1 = 0.91 mol If R1 uses n1 mol O2, generating n1 mol CO2, R2 uses 0.91-n1 mol O2, generating 2 (0.91-n1) mol CO. Since CO/CO2 in the product gas = 2, 2 (0.91-n1)/n1 = 2 n1 = 0.91/2 = 0.455 mol Therefore, total moles of C input = 3 n1 = 1.365 mol O2 required for complete combustion of 1.365 mol C = 1.365 mol (for R1 only) O2 excess % = (1.91 -1365)/1.365 x 100% = 39.9% = 40% .

Related Questions

A passage is given with five questions following it. Read the passage carefully and select the best answer to each question out of the given fouralternatives. Just as space permeates everything in the universe, love permeates every part, every aspect of creation. If there is one answer to the question, “How and why doesthis world exist?” the answer, in one word, is Love. Rather, the answer is Pure Love, since the word love has lost its meaning. Your very existence is an expression of pure unconditional love of the Source (you may call it Consciousness, Creator, God, Divine Self). This is the truth of your being.True love transcends both love and hatred. It is unconditional, unquestioning, boundless, unchanging love. It is overflowing love of the Source for the Source throughall of creation. True love is way beyond the personalized love that two or more individuals assert on one another. Personalized love, though apparently selfless, is rooted in desiresand conditional satisfaction. We have been brought up in a society that judges love based on conditions. We have been made to believe that we can receive love only when we fit into peoplesexpectations. If we are not good enough, we will be deprived of love. These beliefs have influenced the collective psyche of families, groups, communities, and societies since generations to such an extent that love has been reduced tofear of denial. We need to shift from the paradigm of false conditional love to the essence of pure unconditional love . The experience of true love comes with surrender of the false I, in letting go of the feeling of separateness. Without this sacrifice, it is not possible to attain divinelove. When this separate I is discarded, you embrace everything in oneness and catch a glimpse of pure love. True love can be experienced only through giving, not by demanding. People who exist in your life are not here to love you. They are here to remind you that you arethe Source of Love. By knowing that you are the Source of love, you can love yourself, instead of waiting to receive love from the world. Ask yourself, “Why do I need an agent to love myself?” Waiting for the world to love you, is like hiring an agent to love yourself! It is time for you to honor yourself as the Source of love. You have undertaken this human journey to realize and express the boundless love that you truly are. Which of the following statement(s) is/are TRUE about pure love?
In a newly developed innovative idea brought up by CSIR in India, gas turbine exhaust gas are being utilized to convert feedwater into steam. Certain data of the experiment are as follows: mass flow rate of exhaust gas = 40 kg/hr, enthalpy of exhaust gas at the time of their exit from gas turbine is 600 kJ/kg, steam turbine output as measured by brake dynamometer = 60 hp-sec, thermal efficiency of steam power plant is 0.25, efficiency of exhaust gas in converting feedwater into steam is taken as 50%. Find the enthalpy of exhaust gas remaining after they generate steam from feedwater?
Only if the calculated molar mass is higher than the actual molar mass of the solute, the calculated molar mass is considered to be abnormal molar mass.
Read the following passage and answer the item that follows. Your answers to this item should be based on the passage only. In the last two decades, the world's gross domestic product (GDP) has increased by 50 percent, whereas inclusive wealth has increased by a mere 3 percent. In recent decades, GDP-driven economic performance has only harmed inclusive wealth like human capital; and natural capital like forests, land and water. While the world's human capital which stands at 57 percent of total inclusive wealth grew by only 8 percent, the natural capital which is 23 percent of total inclusive wealth declined by 30 percent worldwide in the last two decades. Which of the following is the most crucial inference from the above passage?
A draught of 15mm of water is produced by using a chimney of height 30m. The ambient air and flue gases are at 27oC and 300oC respectively. The coal burned on the grate contains 81% carbon, 5% moisture and remaining ash. Neglect the losses and assume values of burnt products equivalent to the volume of air supplied and for the complete combustion of fuel, find the percentage of excess of air supplied?
In the carbonation of a soft drink, the total quantity of carbon dioxide required is the equivalent of 3 volumes of gas to one volume of water at 0⁰C and atmospheric pressure. Calculate (i) the mass fraction and (ii) the mole fraction of the CO2 in the drink, ignoring all components other than CO2 and water. Basis 1 m3 of water = 1000 kg Volume of carbon dioxide added = 3 m3 From the gas equation, pV = nRT 1 x 3 = n x 0.08206 x 273 n = 0.134 mole. Molecular weight of carbon dioxide = 44 And so weight of carbon dioxide added = 0.134 x 44 = 5.9 kg
20 L of pure water was added to a vessel containing 80 L of pure milk. 36 L of the resultant mixture was then sold and some more pure milk and pure water was added to the vessel in the respective ratio of 7 : 2. If the final quantity of water was 3 liters less than the initial quantity of water in the vessel, what was the quantity of pure milk that was added to the vessel? (in liters)
In the following question, the 1st and the last part of the sentence/ passage are numbered 1 and 6. The rest of the sentence/passage is split into four parts and named P, Q, R and S. These four parts are not given in their proper order. Read the sentence/passage and find out which of the four combinations is correct. 1. Global warming is the rise in average surface temperature of the earth globally. P. It is caused by the greenhouse effect of increased level of greenhouse gases. Q. Deforestation also increases carbon dioxide emissions. R. Greenhouse gases include carbon dioxide, CFCs, etc. S. The increasing use of fossil fuels is a major cause of carbon dioxide emission. 6. Carbon dioxide traps heat and causes the greenhouse effect.
The bar diagram given below shows the sales (in lakhs) of five different products A, B, C, D and E by a company during 2001 and 2005. Which of the following statement(s) is/are correct? I. The sale of product B in 2001 is 56.67 percent more than that of product C. II. The sale of product A in 2001 is 146.67 percent more than that of product E. III. The ratio of the sales of product C in 2001 to that of product D in 2005 is 1 : 7.
Given that, 24 carat gold is pure gold, 18 carat gold is 3/4th of pure gold and 20 carat gold is 5/6th of pure gold, the ratio of the pure gold in 18 carat gold to the pure gold in 20 carat gold is -