Question

Name the following:
$1.$A metal which is preserved in kerosene
$2.$A lustrous colored non-metal
$3.$A metal which can melt while kept on a palm
$4.$A metal which is a poor conductor of heat

Answer 1

Hint: To answer this question we must know the role and meaning of kerosene, lustrous, etc. There are many elements known to us and only few of them have properties which suit the all above conditions individually. Some elements can be preserved in kerosene, some elements are lustrous. Few elements are a poor conductor of heat. We will discuss it below.

Complete answer:
$1.$Sodium $\left( {Na} \right)$ is a metal which is stored in kerosene. Along with this there is another metal which can be stored in kerosene and that is potassium $\left( K \right)$. Sodium is very highly reactive metal and with oxygen $\left( {{O_2}} \right)$ it reacts vigorously. Along with oxygen, it also reacts vigorously with carbon dioxide $\left( {C{O_2}} \right)$ and moisture present in air. It reacts with all of these in such a way that it can cause a fire. That is why it is kept immersed in kerosene because it is non-reactive.
$2.$ Iodine $\left( {{I_2}} \right)$ is a lustrous colored non-metal. Along with this there is another lustrous colored non-metal which is diamond. Iodine $\left( {{I_2}} \right)$ is lustrous because when we goes down the group size increases and due to poor shielding effect there is less interaction between atom and outermost electron so these electrons gets excited by absorbing energy and when they emit energy it appears that they have lustrous surface.
$3.$Gallium $\left( {Ga} \right)$ or cesium $\left( {Cs} \right)$ are two metals which melt when kept on the palm.
$4.$Lead $\left( {Pb} \right)$ or mercury $\left( {Hg} \right)$ are two metals that are poor conductors of heat.

Note:
Lead when reacts with the atmosphere, it forms lead oxide and metal oxides are poor conductors of heat. They are poor conductors of electricity also. It is a soft metal with silvery white and gray color. It is highly toxic in nature and can act as a very strong poison. Due to low melting point Gallium melts on our palm.