PLEASE HELP!! thank you in advance! :)

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

50 pts plz what is the physical state of matter of baking soda.

Which electron configuration represents the electrons in an atom of sodium in the ground state at stp