HELLO RAM LAL
your question is excellent
the two compounds which you have given are both functional as well as ring chain isomers
and the resons are i will explaining you are as follows
as there are two functional isomers in the compound OH and ether,they are functional isomers
Ring chain isomers is also present because cyclobutanol is ring form and other one is chain form right
and also molecular formula is same i,e C4H8O
AND FOR YOUR BETTER UNDERSTANDING I WILL GIVE AN EXAMPLE AND WITH THE FORMULA YOU FIND THE SOLUTION FOR THAT AND WILL GET TO KNOW
1.write all the possible structural isomers of molecular formula C4H8O
soln – the formula is
=> DoU = 2C + 2 + N – X – H
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2
you will get to know the all possible ring chain isomers from this formula of C4H8O
But the above compound you have given is both of them
THANK YOU