If pH of a solution is 5 is it acidic or base?

Acidic.

A pH of 7 is neutral ... and since it is a negative log function (i.e. numbers less than 1)

then the lower the number ... the more acid it is. [pH is a measure of the concentration of H+ ions.]

And to add to your confusion, the pH of neutrality is temperature dependent;

it's 7 at 25 degrees C but 7.4 at 37 degrees C (body temp).