Which of the following gases is responsible for the formation of photochemical smog?
A. Carbon dioxide
B. Ammonia
C. Methane
D. Ozone and PAN
Answer: Option D
Solution (By JKSSB Mock Tests)
Photochemical smog is formed in sunny, dry cities due to the reaction of sunlight with nitrogen oxides and volatile organic compounds (from vehicle exhaust). This produces secondary pollutants like ozone (O₃), peroxyacetyl nitrate (PAN), and aldehydes, which make up the harmful smog.
Explanation:
Calorific value is determined using a bomb calorimeter, where a known mass of fuel is burnt in excess oxygen in a sealed bomb, and the heat released is absorbed by a known mass of water. Temperature rise is measured. Corrections for cooling, wire, and acid formation are applied. Units: kJ/kg or kJ/mol. The bomb calorimeter works at constant volume.
Explanation:
Electron affinity is the energy change when an electron is added to a neutral gaseous atom. It represents the tendency to gain electrons. Ionization energy is the energy to remove an electron. Electropositivity and metallic character relate to the tendency to lose electrons and form positive ions.
Explanation:
Enzymes are proteins that act as catalysts, exhibiting high specificity for substrates (lock-and-key model). They are not consumed, denature at high temperatures, and are organic. Examples: amylase for starch, pepsin for proteins.
No comments yet. Be the first to start the discussion!