To support the tungsten filament in an electric bulb,the metal used is:

For $Cu_{2}Cl_{2}$ and $CuCl_{2}$ in aqueous medium,which of the following statements is correct?

Among $CrO$,$Cr_2O_3$,and $CrO_3$,the sum of spin-only magnetic moment values of basic and amphoteric oxides is . . . . . . . . $10^{-2} \ BM$ (nearest integer).
(Given atomic number of $Cr$ is $24$)

Acidified potassium permanganate solution oxidises oxalic acid. The spin-only magnetic moment of the manganese product formed from the above reaction is $.... \, B.M.$ (Nearest Integer)

The fusion of manganese dioxide with $KOH$ in the presence of an oxidizing agent like $KNO_3$ yields a compound. Identify the compound and its color.

The fusion of chromite ore $(FeCr_{2}O_{4})$ with $Na_{2}CO_{3}$ in air gives a yellow solution upon addition of water. Subsequent treatment with $H_{2}SO_{4}$ produces an orange solution. The yellow and orange colours,respectively,are due to the formation of