NO3-
NO2
NO2-
The question pertains to understanding which oxide of nitrogen can be harmful to plant leaves and can hinder photosynthesis. Let us evaluate each option:
Given these evaluations, NO2 is the oxide of nitrogen that can damage plant leaves and retard photosynthesis. Therefore, the correct answer is:
NO2
Method used for separation of mixture of products (B and C) obtained in the following reaction is: 
Which one of the following graphs accurately represents the plot of partial pressure of CS₂ vs its mole fraction in a mixture of acetone and CS₂ at constant temperature?

In the given figure, the blocks $A$, $B$ and $C$ weigh $4\,\text{kg}$, $6\,\text{kg}$ and $8\,\text{kg}$ respectively. The coefficient of sliding friction between any two surfaces is $0.5$. The force $\vec{F}$ required to slide the block $C$ with constant speed is ___ N.
(Given: $g = 10\,\text{m s}^{-2}$) 