Most hydrocarbons are .....than water?

Question

As a general rule, most hydrocarbons are ....than water?

A more volatile

B less volatile

C there is no general rule

Answer 1

A, more volatile. definitely. all hydrocarbons can get combusted (burn) , not water.

Answer 2

Volatility is how easily a substance vaporizes. A more volatile substance vaporizes faster and with less energy required.

Volatility is dependent on the strength of if the attraction between molecules, also called intermolecular forces, abbreviated IMFs. IMFs between covalent molecules are of three types, and are listed in order of increasing strength: Dispersion forces or temporary dipole attractions, polar bonds or permanent dipole attractions, and hydrogen bonding. All three are attractive forces.

Dispersion forces are caused by the electron cloud of a molecule shifting back and forth across a molecule. All covalent molecules experience dispersion forces, but it is stronger in larger, heavier molecules.

Polar bonds are caused when a more electronegative atom in a molecule pulls electrons towards it, creating distinct negative and positive zones, which are attracted to other poles on other atoms.

Hydrogen bonds are caused when a hydrogen atom is bonded to an oxygen, nitrogen, or fluorine atom. The large electronegativity difference and relatively small sizes of the atoms result in drastic poles.

Hydrocarbons are molecules containing only hydrogen and carbon. Because of their structure, they are not polar and do not experience hydrogen bonding. Water is extremely polar and does experience hydrogen bonding. Because the hydrocarbons have weaker IMFs, their molecules are easier to separate, and so are more volatile.

Answer 3

C

Answer 4

B

Answer 5

There is a general rule to this, smaller hydrocarbons, ethane and ethene for example, are more volatile than water compared to larger hydrocarbons.

The question is tricky and non-factual. Since hydrocarbons are able to be (theoretically) infinitely long, most hydrocarbons (being huge) would be less volatile than water.

However, at around the same molecular size, hydrocarbons do not possess a hydrogen attached to a highly electronegative atom (eg: O or N atoms), and are therefore unable to form hydrogen bonds among each another. In this case, hydrocarbons are more volatile than water. The ability to form hydrogen bonds accounts greatly for the reduced volatility of water and other of such able organic compounds.