alcohols concentration reagent single step transition state atomic weights electron acceptor protons heat flow sodium methanol room temperature organic chemistry Organic dehydration organic reactions reagents acetone electrons covalent bonds equilibrium substrates atoms selectivity cells catalytic hydrogenation molecules local anesthetic journal article hydrogen gas chemistry carbons acids and bases aspirin electrophile chromosomes chirality cell cycles chemical reaction diels alder reaction hydrogen bonds cesium amino acids acyl esters hydrogen peroxide dna molecule cytosine ketone phosphate krebs cycle joules metabolism reactants temperatures ammonia atom proteins highest energy dehydration reaction chemical reactions hydrogen constituents thymine salicylic acid water molecules living organisms chemicals correlation junior chemistry nucleophile synthesis derivatives alcohol activation energy carbon dioxide glucose exothermic reaction alkenes oxidation atomic mass byproducts electron pair presence isomer alkyne racemic mixture intermediates electron density organic solvents cis ethers pyruvate alkene carbon atoms molecule protons neutrons and electrons catalyst catalysts solvent