What is the color of copper carbonate salt?

In which state does the element phosphorus exist at room temperature?

Name two metals which are purified by electrolytic refining. Mention the anode,cathode and the electrolyte used in the refining process. At which electrode would the pure metal be deposited?

What are the constituent elements of Magnalium?

When a metal $X$ is treated with cold water, it gives a basic salt $Y$ with molecular formula $XOH$ (molecular mass $= 40$) and liberates a gas $Z$ which easily catches fire. Identify $X$, $Y$, and $Z$, and write the chemical reaction involved.

What type of oxide is $H_{2}O$?