The reaction shown is a free radical halogenation reaction. This method is unsuitable for the preparation of fluoroarenes because of the high reactivity of fluorine. Fluorine is so reactive that it is difficult to control the reaction, leading to multiple substitutions. In this reaction, the free radical is formed by using the metal Fe in dark conditions. For the other halogens, the reaction can be controlled to obtain the corresponding haloarenes.
Consider a water tank shown in the figure. It has one wall at \(x = L\) and can be taken to be very wide in the z direction. When filled with a liquid of surface tension \(S\) and density \( \rho \), the liquid surface makes angle \( \theta_0 \) (\( \theta_0 < < 1 \)) with the x-axis at \(x = L\). If \(y(x)\) is the height of the surface then the equation for \(y(x)\) is: (take \(g\) as the acceleration due to gravity)
A constant voltage of 50 V is maintained between the points A and B of the circuit shown in the figure. The current through the branch CD of the circuit is :