Although CHsubscript4 has 4 hydrogens, it is an acid. Why?

It is NOT an acid. Did you make a typo or misread your notes/question? It isn't an acid because CH4 is not a proton donor.

sorry, that's what i meant-why isn't it an acid?

No problem! CH4, also known as methane, is not considered an acid because it does not contain any acidic properties. Acids are substances that can release hydrogen ions (H+) when dissolved in water, which can then donate the hydrogen ion to another substance. Methane does not have any hydrogen ions that can be released or donated, so it is not classified as an acid. Instead, CH4 is a hydrocarbon compound consisting of one carbon atom (C) bonded with four hydrogen atoms (H) and is considered a simple alkane.