Chemistry in Automobiles: For an internal combustion engine to move a vehicle down the road, it must convert the energy stored in the fuel into mechanical energy to drive the wheels. In your car, the distributor and battery provide this starting energy by creating an electrical "spark", which helps in combustion of fuels like gasoline. Below is the reaction depicting complete combustion of gasoline in full supply of air:
3.1 Which of the following are the products obtained from the reaction mentioned in the above case?
Product ‘X’ Product ‘Y’
a) CO 2 H 2 O 2
b) H 2 O CO
c) CH 3 OH H 2 O
d) CO 2 H 2 O
3.1 → (d)
3.2 Identify the types of chemical reaction occurring during the combustion of fuel:
a) Oxidation & Endothermic reaction
b) Decomposition & Exothermic reaction
c) Oxidation & Exothermic reaction
d) Combination & Endothermic reaction
(c) Oxidation & Exothermic reaction
Addition of Oxygen to a Substance or removal of Hydrogen from a substance is called Oxidation
Reaction in which heat energy is produced is called Exothermic Reaction
3.3 On the basis of evolution/absorption of energy, which of the following processes are similar to combustion of fuel?
a) Photosynthesis in plants
b) Respiration in the human body
c) Decomposition of vegetable matter
d) Decomposition of ferrous sulphate.
(a) (ii) & (iii)
(b) (i) & (ii)
(c) (iii) & (iv)
(d) (ii) & (i)
3.3 → (a) (ii) & (iii) → Respiration in the human body and Decomposition of vegetable matter
All these processes involve evolution of energy
3.4 ‘A student while walking on the road observed that a cloud of black smoke belched out from the exhaust stack of moving trucks on the road.’ Choose the correct reason for the production of black smoke:
a) Limited supply of air leads to incomplete combustion of fuel
b) Rich supply of air leads to complete combustion of fuel.
c) Rich supply of air leads to a combination reaction.
d) Limited supply of air leads to complete combustion of fuel.
3.4 → (a) Limited supply of air leads to incomplete combustion of fuel
3.5 ‘Although nitrogen is the most abundant gas in the atmosphere, it does not take part in combustion’. Identify the correct reason for this statement.
a) Nitrogen is a reactive gas
b) Nitrogen is an inert gas
c) Nitrogen is an explosive gas
d) Only hydrocarbons can take part in combustion
3.5 → (b) Nitrogen is an inert gas
The triple bond in nitrogen is too strong to be broken and hence it is inert (does not react)