What is obtained by the oxidation of ethyl alcohol with $K_2Cr_2O_7$?

Amongst the following compounds,identify which are insoluble,partially soluble,and highly soluble in water:
$(i)$ phenol,$(ii)$ toluene,$(iii)$ formic acid,$(iv)$ ethylene glycol,$(v)$ chloroform,$(vi)$ pentanol.

Identify the product of the following reaction: $\gamma$-butyrolactone + $BrMg-(CH_2)_4-MgBr$ $\xrightarrow[(ii) H_3O^{+}]{(i) THF}$

Which of the following alcohols is the most acidic?

Identify the major products $A$ and $B$ respectively in the following set of reactions.

From the following,how many compounds contain at least one secondary alcohol? Choose the correct answer from the options given below: