Question

For many years after they were discovered, it was believed that the noble gases could not form compounds. Now we know that belief to be incorrect. A mixture of xenon and fluorine gases, confined in a quartz bulb and placed on a windowsill, is found to slowly produce a white solid. Analysis of the compound indicates that it contains \({\rm{77}}{\rm{.55\% }}\)Xe and \({\rm{22}}{\rm{.45\% \;F}}\)by mass.

(a) What is the formula of the compound?

(b) Write a Lewis structure for the compound.

(c) Predict the shape of the molecules of the compound.

(d) What hybridization is consistent with the shape you predicted?

Short answer

a. The molecular formula of the compound is \({\rm{Xe}}{{\rm{F}}_{\rm{2}}}\).

b. The Lewis structure is as follows:

c. The shape of the molecule is linear.

d. The hybridization is\({\rm{s}}{{\rm{p}}^{\rm{3}}}{\rm{\;d}}\).

Step-by-step solution

Definition of Concept

Lewis structure:A Lewis Structure arequite generalised representation of the valence shell electrons in a molecule.

Hybridization: When pure orbitals (having comparable energy) are mixed together to produce an equivalent amount of impure orbitals (with equal energy and definite geometry).

Find the formula of the compound

(a)

We will put the given data in tabular form in the question to find the molecular formula.

Considering the given information:

\({\rm{\% }}\)of\({\rm{Xe = 77}}{\rm{.55}}\)

\({\rm{\% }}\)of\({\rm{F = 22}}{\rm{.45}}\)

Atomic mass of\({\rm{Xe = 131}}{\rm{.293amu}}\)

Atomic mass of\({\rm{F = 18}}{\rm{.99amu}}\)

Now,

Therefore, there is one Xe atom and two F atoms.

So, the formula is\({\rm{Xe}}{{\rm{F}}_{\rm{2}}}\).

Draw a Lewis structure for the compound

Because fluorine has seven valence electrons and xenon has eight in its outermost orbit, the two fluorine atoms share one electron with xenon to form a noble gas.

Therefore, the following is the Lewis dot structure:

Predict the shape of the molecules of the compound

The Lewis dot structure is based on the Lewis dot structure.

Number of electrons in a bond pair\({\rm{ = 2}}\)

The number of electrons in a lone pair,

\(\begin{array}{l}{\rm{ = }}\frac{{{\rm{ Valenceelectronofcentralatom Xe - Number f bondpairelectron }}}}{{\rm{2}}}\\{\rm{ = }}\frac{{{\rm{8 - 2}}}}{{\rm{2}}}\\{\rm{ = 3}}\end{array}\)

Total pair of electron\({\rm{ = 5}}\)

Structure = Trigonal bipyramidal

Therefore, the required we can see that the molecule's shape is linear.

Find the hybridization of the molecule

The Lewis dot structure is based on the Lewis dot structure.

Number of electrons in a bond pair\({\rm{ = 2}}\)

The number of electrons in a lone pair,

\(\begin{array}{l}{\rm{ = }}\frac{{{\rm{ Valenceelectronofcentralatom Xe - Number f bondpairelectron }}}}{{\rm{2}}}\\{\rm{ = }}\frac{{{\rm{8 - 2}}}}{{\rm{2}}}\\{\rm{ = 3}}\end{array}\)

Total pair of electron\({\rm{ = 5}}\)

Structure = Trigonal bipyramidal

Therefore, the required hybridization is\({\rm{s}}{{\rm{p}}^{\rm{3}}}{\rm{\;d}}\).