The difference between the boiling point of a pure solvent and the boiling point of a solution of a nonelectrolyte in the same solvent is called the , a colligative property. A. boiling-point elevation
B. freezing-point depression
C. molar freezing-point constant
D. molal melting-point constant
E. molal boiling-point constant

According to arrhenius theory of acid and bases, an acid is a proton donor, while base donates hydroxyl ions. further, acid and base reacts to form salt and water.consider following example.hcl    +      h2o          →      cl-          +      h3o+here, hcl has donated a proton, hence it is an acid.now consider following reactionhcl      +      naoh            ↔      nacl      +        h2oin this reaction, hcl donates proton, hence it is acid. on other hand, naoh donates hydroxyl ion (i.e. hence it is a base.   

Answerthe famous eqn e=mc^2 is what appllies    

The only byproduct of using pure hydrogen as fuel is water,often in vapor form