What is ch3ch2chch3ch2oh?

As given in the question ; nothing;!!!!

If you mean 'CH3- CH2-CH=CH3-CH2OH , then it is still incorrect. However, note the use of CAPITAL letter.s

Structurally the molecule doesn't exists.

Structurally it is CH3-CH2-CH=CH-CH2OH , which by name is ' Pent-2-enol. or Pent-2-ene-1-ol.