Halkoarenes & Haloarenes MCQs for NEET — Chemistry Questions with Answers

In the Grignard reaction, magnesium forms an organometallic bond. Grignard reagents have the general formula RMgX, where R is an organic group and X is a halogen.

HF is liq. Because of int . molec. H - Bond

(d)    Due to small size of $\mathrm{He}$, it escapes from interstitial spaces/voids of 

         molecular lattice of quinols.

The stability decrease in the order $I_3^{-}$ > $B{r}_3^{-}$ > $C{l}_3^{-}$ > $F_3^{-}$ 

In fact no $F_3^{-}$ compounds are known,because flourine has no available d-orbitals and therefore can not expand its octet.

Water shows unusual physical properties due to hydrogen bonding between the water molecules.

Hydrogen fluoride (HF) is a liquid at room temperature due to the strong intermolecular hydrogen bonding present between HF molecules. The small size of the fluorine atom allows the hydrogen bond to form easily, resulting in a higher boiling point compared to other hydrogen halides.

(1)

Hydrofluoric acid won't eat through plastic

The boiling points of $HF,HCl,HBrandHI$ follow the order $HF>HI>HBr>HCl$.
HF is hydrogen bonded, thus has highest boiling point, and it is liquid at or below 19oC. The remaining hydrogen halides are gaseous and their boiling points depend on the van der waal's forces. Larger the size (or molecular mass), greater are the van der Waal's forces, hence higher is the boiling point.