An element $A$ forms two oxides $AO$ and $AO_2$. The oxide $AO$ is neutral,whereas the oxide $AO_2$ is acidic in nature. Would you call element $A$ a metal or a non-metal?

Which ore is concentrated by the froth flotation process?

Generally,non-metals are not conductors of electricity. Which of the following is a good conductor of electricity?

$A$ metal $E$ is stored under kerosene oil. When a small piece of it is left open in the air,it catches fire. When the product formed is dissolved in water,it turns red litmus blue.
$(i)$ Name the metal $E$.
$(ii)$ Write the chemical equations for the reaction when it is exposed to air and when the product is dissolved in water.
$(iii)$ Explain the process by which the metal is obtained from its molten chloride.

During the refining of copper by electrolysis,copper deposits at the $....$.

Which mixture of two gases,taken in equal proportions in a gas jar,reacts in the presence of sunlight?