What is ch2chch(ch3)ch3?

The chemical notation "CH2CHCH(CH3)CH3" represents the alkane pentane, which has 5 carbon atoms in a straight chain. The molecule is made up of carbon (C) and hydrogen (H) atoms with specific bonds between them, forming a saturated hydrocarbon. In this case, "CH2" represents a methylene group, "CH" a methine group, and "(CH3)" a methyl group.