A compound containing only carbon, nitrogen, and hydrogen is analyzed to contain 58.82% carbon, 27.45% nitrogen, and 13.73% hydrogen (by mass), What is its simplest formula?

When given percents for an empirical formula problem, first consider all the percents as grams.

58.82% carbon —> 58.82 g carbon
27.45% nitrogen —> 27.45 g nitrogen
13.73% hydrogen —> 13.73 g hydrogen

Then convert the grams of all the elements to moles, based on their molar masses.

Carbon - 58.82 g / 12.01 g/mol = 4.898 mol carbon

Nitrogen - 27.45 g / 14.01 g/mol = 1.959 mol nitrogen

Hydrogen - 13.73 g / 1.008 g/mol = 13.62 mol hydrogen

Then divide all of the mole numbers by the smallest number of moles, which is in this case, the 1.959 mol of nitrogen.

Carbon - 4.898 / 1.959 = 2.5

Nitrogen - 1.959 / 1.959 = 1

Hydrogen - 13.62 / 1.959 = 7

You want whole numbers for all of your mole numbers, so multiply all of them by 2, since 2.5 isn’t a whole number.

Final C5N2H14

Spontaneity tell us the direction of the reaction, but not how fast it goes. gibbs free energy brings together enthalpy, entropy and temperature in one easy formula. g = h - ts. and, finally the sign of delta g is always negative for a spontaneous reaction.