Which of the following interhalogen compounds is in liquid state at room temperature?

Which of the following is incorrect about cyanogen gas?

When $1 \ mol$ of fluorine reacts with $2 \ mol$ of hot and concentrated $KOH$,the products obtained are $KF$,$H_2O$,and $O_2$. The molar ratio of $KF$,$H_2O$,and $O_2$ produced is respectively:

$SF_{6}$ is known but $SCl_{6}$ is not. Why?

Bromine is obtained on a commercial scale from

To purify fluorine gas,fumes of $HF$ are removed by