[OTI]

So here are some of the problems I am unsure about.

Why does sugar dissolve in water but not gasoline?
Why do metals dissolve easily in acid but not water or base?
Why is iodine more soluble in air than water?
Why do metals stick to each other very easily?

Thanks

[mikasaur]

Hello and welcome to the forum!

Before we can help you, you must show us that you've put some thought into your questions. We can't do your homework for you!

What are your initial thoughts for each of these questions? Can you break them down into what they're really trying to get at, e.g. how is water different from gasoline and what does that mean for something like sugar?

[OTI]

Sure.

my answers go in order from the ones I am surer about to the ones I have no clue about.

For why metals stick to each other easily, I was thinking something along the lines of metal cations and the electron sea keeping each other in line. I'm not sure whether the problem refers to one type of metal or different types of metal, but I was thinking that metals should stick to each other because they both have cations and electron seas, and they would all be attracted to each other (Like one's cations to the other's electron sea).

For the sugar one, sugar and water both have hydrogen bonds while gasoline has only carbon atoms and hydrogen atoms I think. Maybe there is something to do with the molecular dipole or something.

I seriously have no idea about the metal dissolving one. I get that acids scary because they destroy stuff, but I don't really get why. Same for properties of bases. I do know, however, that metals don't dissolve easily in water because metals with metallic bonds aren't polar while water is, and the electrons in the electron sea would rather be near the fully exposed cations with a full charge rather than the partially charged hydrogen in water.

[Arkcon]

Why do metals dissolve easily in acid but not water or base?

This factoid is often quoted in beginning chemistry.  And its just wrong, on the face of it.  Some metals dissolve in some acids because they undergo a chemical reaction and become a soluble salt.  Many metal hydroxides are insoluble salts.  Its just plain cheating to ponder why one thing dissolves in a reagent, when the reagent changes the metal into something else.

[Enthalpy]

Why does sugar dissolve in water but not gasoline?
Why is iodine more soluble in air than water?
Why do metals stick to each other very easily?

For sugar, you could have a look at hydrogen bonds and at polar solvents, for instance on Wiki.

I wouldn't say "soluble in air". Air interacts very little with these vapours, and you'd get the same amount of vapour in argon or vacuum instead of air. At equilibrium, the nature and temperature of the solid iodine or liquid water determine the amount of vapour, or better said, its partial pressure. This is very different from sugar in water where interactions do everything.

Do metals stick easily to each other? That's not common experience! If you put two metal parts against an other they are easy to separate. Or do you mean: metal atoms in a solid? Then it would depend on each metal, as for instance Hg has a vapour pressure easy to observe and used in technology.