Metre scales are made up of which alloy?

Which of the following has conductivity and appearance like that of copper metal?

Pick out the incorrect statement:

Describe the preparation of potassium dichromate from iron chromite ore. What is the effect of increasing $pH$ on a solution of potassium dichromate?

Which among the following statements is incorrect for interstitial compounds?
$1$. They are very hard and rigid
$2$. They have higher melting point than pure metal
$3$. They do not show conductivity
$4$. They are chemically inert

Potassium permanganate on heating at $513 \ K$ gives a product which is :