How many moles of C is needed to react with 5.0 moles of H to form C3H8

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

Identify the electromagnets with poles that are reversed from the electromagnet shown above

The excretory system,need answers for all: )