Cu and Ag exist as sulphides though they occupy lower positions in the electrochemical series - why?

How are the elements occupying higher positions of the electrochemical series extracted?

Li occupies higher position in the electrochemical series of metals as compared to Cu since

Li occupies higher position in the electrochemical series of metals as compared to Cu since -

Why are the elements at higher positions in the electrochemical series not available in free state in nature?

Explain why HF forms hydrogen bonding with acetylene even though it is non-polar in nature.

The dipole moment of fluorobenzene is lower than that of iodobenzene, even though fluorine is more electronegative than iodine - explain.

A voltage V_0sinomegat is applied to a series LCR circuit, Derive the expression for the average power dissipated over a cycle. Under what condition is (i) no power dissipated even though the current flows through the circuit,(ii) maximum power dissipated in the circuit?

An electric current is passed through three cells in series containing respectively solutions of copper sulphate, silver nitrate and potassium iodide. What weights of silver and iodine will be liberated while 1.25 g of copper is being deposited ?

A metal rod PQ is resting on the rails A'B' and positioned between the poles of a permanent magnet. The rails, the rod and the magnetic field are in three mutually perpendicular directions. A galvanometer G connects the rails through a switch K. Length of the rod = 15 cm, B = 0.50 T, resistance of the closed loop containing the rod = 9.0 mOmega . Assume the field to be uniform. With K open and the rod moving uniformly, there is no net force on the electrons in thr rod PQ even though they do experience magnetic force due to the motion of the rod. Explain.