which pair of substances are most likely to obey Raoult's Law?

Question

C5H12 and C6H14
H3PO4 and H20
C4H9COOH and C5H12
C5H12 and H20
C4H9COOH and H20

How do I go about figuring this out? What should I be comparing, differences in molar masses, polarity, etc...?

Answer 1

I would choose substances that are alike in ability to dissove miscibily.

Pentane and water is no..for example.

Butanoic acid and pentane is another not likely to dissolve.