Tag: formal charge

Questions Related to formal charge

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

A molecule with highest bond energy is:

  1. Fluorine

  2. Chlorine

  3. Bromine

  4. Iodine

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Bond dissociation energy in $KJ mol^-1$
$F _2-158$
$Cl _2-244$ 
$Br _2-93$ 
$I _2-151$ 
Hence, in order of decreasing bond strength: 
$Cl _2>Br _2>F _2>I _2$
Fluorine is an anomaly. 

Bond strength decreases from chlorine to iodine as down the group, the atomic size becomes larger and thus the valence electron orbitals become more diffused, causing the overlap of orbitals to become less effective. Therefore the halogen-halogen bond becomes weaker from chlorine to iodine.Fluorine is an exception due to its extremely small size. The F-F bond length is so short that the lone pairs of electrons on the fluorine atoms repel each other and weakens the F-F bond. 

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

In which of the following molecules partial charge separation does not take place?

  1. Chlorine

  2. Hydrochloric acid

  3. Water

  4. Ammonia

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cl molecules are covalent in nature so it is non polar molecule. Non polar compound consists of molecules linked through chemical bonds arranged in such a way that the distribution of charges are symmetrical. Non polar bonds do not exhibit polarity and do not form ions in their solution. These compounds do not dissolve in water which is a polar molecule.

Multiple choice chemistry chemical bonding and structure formal charge basics of chemical bonding types of bonds

The partial charge separation between the bonded atoms gives rise to ___________ in that compound.

  1. covalent character

  2. coordinate character

  3. ionic character

  4. none of these

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Partial charge separation between the bonded atoms gives rise to ionic character in the molecule due to the electronegativity difference, a quite small degree of polarization occurs.