Efficiency of Fuel

Q. ntif enthalpies of formation for c2h4 (g) , co2 (g) and h2o (l) at 25 degree centigrade 1 atm pressure are 52, -394 and -286 kj/mol respectively, then enthalpy of combustion of c2h4(g), will be n

Q. What are hydrocarbons?

Q. The calorific values of wood, diesel, natural gas and charcoal vary in the order –

1. Natural gas >Diesel > Charcoal> Wood
2. Wood > Diesel > Natural gas > Charcoal
3. Wood > Diesel > Charcoal > Natural gas
4. Natural gas >Diesel> Wood > Charcoal

Q. If a diesel sample contains 75% cetane and 25% alpha-methyl naphthalene, its octane number is:

1. 25
2. 75
3. 50
4. 66.6

Q.

Name the allotropic form of carbon which decolourises sugar.

Q. What is the octane number of triptane?

1. 100
2. 25
3. 45
4. 125

Q. What is the octane number of $n$-nonane?

1. 0
2. $-20$
3. 100
4. more than 100

Q. What is open chain isomers for propone

Q.

Difference between CNG and LPG

Q. Which of the following are the properties of methane ?

1. Colourless gas
2. Odourless gas
3. Less soluble in water
4. All of the above

Q. Cetane number is the percentage of cetane (octa-decane) in a given diesel sample.

1. True
2. False

Q. A sample of petrol is a mixture of $30\%$ n-heptane and $70\%$ iso-octane. The sample has octane number

1. $30$
2. $70$
3. $15$
4. $35$

Q. The octane number of gasoline is defined as the percentage of n-heptane present in a mixture of iso-octane and n-heptane, when the mixture has the same knocking in the engine, as the gasoline under examination.

1. True
2. False

Q.

Which of the following is the chemically inactive allotropic form of carbon?

1. diamond

2. coal

3. charcoal

4. animal charcoal

Q. A fuel has octane no. of $60$. This indicates that fuel has the knocking tendency equal to:

1. $60$% n-heptane + $40$% iso octane
2. $60$% n-octane + $40$% isoheptane
3. $60$% isooctane + $40$% n-heptane
4. $60$% isoheptane + $40$% n-octane

Q.

Raghav is planning to start a bonfire in the evening and has collected lot of dry wood and leaves. He fetches a matchbox and starts the fire. In this example, what do you think is the activation energy?

1. Collecting dry wood and leaves

2. Pouring kerosene on firewood

3. Igniting the matchstick

4. Availability of oxygen

Q. Which of the following has highest octane number

1. n-hexane
2. n-heptane
3. iso-octane
4. n-heptane and iso-octane mixed in ratio $50:50$

Q. The hydrocarbon iso-octane which has good resistance to knocking even in highest compression motors is arbitrarily given an octane number of 0. Whereas n-heptane which knocks the maximum is arbitrarily given the value of 100.

1. True
2. False

Q. Octane number can be changed by :

1. All of these
2. alkylation
3. cyclisation
4. isomerisation

Q. Octane number of iso-octane is:

1. 50
2. 25
3. 100
4. 150

Q. Which of the following can be used to increase the octane number?

1. Increasing the percentage of branched or cycloalkanes
2. By addition of BTX or TEL
3. By addition of powder alcohol (ethanol)
4. All of the above.

Q. The calorific values of petrol and CNG are 45000 kJ/kg and 50, 000 kJ/kg, respectively. If you have vehicle which can run on petrol as well as CNG, which fuel will you prefer and why? [3 marks]

Q. Select the correct option about the Octane number of the organic compound.

1. Saturated compound $>$ Unsaturated compound
2. Saturated compound $<$ Unsaturated compound
3. Saturated compound $=$ Unsaturated compound
4. Both A and B

Q. Which one is true for the octane number of following organic compounds?

1. Aromatic Compound $>$ Aliphatic compound
2. Aromatic compound $=$ Aliphatic compound
3. Aromatic compound $<$ Aliphatic compound
4. None of the above

Q. With increase in octane number:

1. cetane number decreases
2. activation energy increases
3. both A & B
4. neither A nor B

Q. Octane number of petrol can be improved by adding or mixing it With which of the following chemicals ?

1. Pyrene
2. $E{t}_{4}Pb$
3. $C{H}_{3}OC(C{H}_3{)}_3$
4. 1-methyl naphthalene

Q. The correct relation of the Octane number for the following is:

1. straight chain $>$ branched chain
2. straight chain $<$ branched chain
3. straight chain $=$ branched chain
4. both A and B

Q. The RON/MON values of $n$-heptane is:

1. $100$
2. $50$
3. $1000$
4. $0$

Q.

Which of the following is correctly matched?

1. $\begin{array}{cc}\text{Element}& \text{Uses}\\ \text{Hydrogen}& \text{Fuel}\\ \text{Chlorine}& \text{Bleaching}\\ \text{Nitrogen}& \text{Fertilizer}\\ \text{Oxygen}& \text{Decomposition}\end{array}$

2. $\begin{array}{cc}\text{Element}& \text{Uses}\\ \text{Hydrogen}& \text{Fuel}\\ \text{Chlorine}& \text{Disinfectant}\\ \text{Nitrogen}& \text{Preserving food}\\ \text{Oxygen}& \text{Combustion}\end{array}$

3. $\begin{array}{cc}\text{Element}& \text{Uses}\\ \text{Hydrogen}& \text{Fuel}\\ \text{Chlorine}& \text{Combustion}\\ \text{Nitrogen}& \text{Preserving food}\\ \text{Oxygen}& \text{Disinfectant}\end{array}$

4. $\begin{array}{cc}\text{Element}& \text{Uses}\\ \text{Hydrogen}& \text{Disinfectant}\\ \text{Chlorine}& \text{Fuel}\\ \text{Nitrogen}& \text{Decomposition}\\ \text{Oxygen}& \text{Preserving food}\end{array}$

Q. Introduction of double or triple bond decreases the value of octane number.

1. True
2. False