Question

Indicate which is more soluble in ethonal:

acetic acid CH3COOH or
stearic acid C17H35COOH

I think acetic acid maybe more soluble but I don't know why

Answer 1

Like dissolves like.
CH3COOH is more like ethanol (or is that ethanal--it makes no difference in the answer) than C17H35COOH. The last molecule, stearic acid, is a long long chain while both ethanol and CH3COOH are small molecules.

Answer 2

so they are the same and both dissolve in ethanol or acetic acid dissolves in ethanol because they are small molecules

Answer 3

I'm not sure you said in your statement what I said in mine so I'll repeat mine another way.
Acetic acid is more soluble in ethanol than stearic acid BECAUSE acetic acid is like ethanol in terms of side and molar mass. Stearic acid may dissolve somewhat in ethanol but ethanol is C2H5OH whereas stearic acid is that long long chain of C17H35COOH. It dissolves a little because of the COOH group BUT C17H35 makes it look more like a hydrocarbon than an alcohol or an acid.