Why is gasoline lighter than water? It's a bigger molecule. Is it intermolecular forces and interactions?

Question

Correct me if I'm wrong, but it evaporates more than water because water stores extra energy in it's bonds right? Is that the only reason? Then why does gasoline rise above air if it is such a big molecule? Does it? Okay, if it doesn't then why does Carbon Tetrachloride, which is obviously heavier than most air rise to the ozone to deplete it? I know dust rises because it is big and catches wind like a kite. Is it the same reasoning?

Thankyou in advance!

Answer 1

Gasoline evaporates more easily because the hydrogen-hydrogen attraction (gasoline molecules basically present their hydrogens to the world) is not as strong as the polar interactions between water molecules. Gasoline is non-polar and water is polar. So, yes, water-water interactions take more energy to overcome - it takes a higher temp to evaporate or to boil water.

Gasoline is less dense mostly because C=12 and O=16. Most gasoline molecules have monomers of CH2 or CH while water is H2O. so the with O weighing 33% more than C and having a similar ratio of H, water weighs more.

Gasoline doesn't rise above air. In stagnent air, it stays low. The Electrical Code recognizes this in a number of ways - water heaters in garages must be elevated 18" (because people store gasoline and lawn mowers in garages), and the high-risk area around around a gasoline transfer point is much bigger at the ground than in the air). But air moves around tremendously inside of buildings and outside and that mixes all the gases.

Carbon Tet (CCL4) is very dense but is also mixed in the atmosphere by winds and updrafts.

Look at some cave research to get a good idea of just how mixed most all other air is. I've measured distinct layers of 8% CO2 laying just below atmospheric air in such an stagnent environment. The evaporation and dispersion of gasoline, etc in the air is all about convection, not pure diffusion which is very slow and can be be overcome by density differences (as in the separation of U-235 from U-238 in specialized equipment.

Answer 2

gasoline is lighter than water beacuse:
1. it is a large molecule as compared to water.
2. the large surgace are allows it be less dense.

Answer 3

larger atomic mass does not correlate to actual fluid density or vapor pressure.

Density is the key. Gasoline in en masse is less dense than water.

Answer 4

it is hydrogen bonding. sturdy affinity of an electron pair from an oxygen of a water molecule to a great can charge of hydrogen of yet another water molecule creates a sturdy bond.

Answer 5

Gasoline is lighter than water because gasoline is basically an oil.

Answer 6

It is a "lighter" molecule.

Look up Mayonnaise to understand Chemistry LOL 8-)