An organic compound with molecular formula $C_7{H}_{8}O$ dissolves in $NaOH$ and gives characteristic colour with $FeC{l}_3$. On treatment with $B{r}_2$, it gives tribromo product  $C_7{H}_{5}OB{r}_3$. The compound is 

Identification of Organic Compound

An organic compound with molecular formula C₇H₈O dissolves in NaOH and gives a characteristic colour with FeCl₃. On treatment with Br₂, it gives tribromo product C₇H₅OBr₃. The compound is p-cresol (4-methylphenol).

This is because the compound is a phenol derivative which reacts with NaOH to form a phenolate ion (soluble in alkali) and gives violet colouration with FeCl₃. The activated aromatic ring readily undergoes tribromination in presence of bromine, producing the tribromo derivative.