How do i know if something is a compound, element, or mixture from looking at a diagram like this?

Nitrogen dioxide reacts with water to form nitric acid and nitrogen monoxide according to the equation: 3no2(g)+h2o(l)→2hno3(l)+no(g) part a suppose that 4.2 mol no2 and 0.50 mol h2o combine and react completely. which reactant is in excess? express your answer as a chemical formula. nothing

This chart represents the melting point of several substance. what besy explains the high melting point of the salt?

How many miles of water are produced if 5.43 mol pbo2 are consumed