The table shows the atomic number and boiling points of some noble gases. Gas helium neon argon krypton xenon Atomic number 2 10 18 36 54 Boiling point / C o - 269 - 246 - 186 - 153 - 107 Xenon forms a number of covalently bonded compounds with fluorine. Define the terms covalent bond.

A chemical bond is the attractive force which holds various constituents (atoms, ions, etc.) together in different chemical species. The bond formed by mutual sharing of electrons between two atoms so as to attain noble gas configuration is called covalent bond.

The table shows the atomic number and boiling points of some noble gases. Gas helium neon argon krypton xenon Atomic number 2 10 18 36 54 Boiling point / C o - 269 - 246 - 186 - 153 - 107 Xenon forms a number of covalently bonded compounds with fluorine. Draw a dot-and-cross diagram for xenon tetrafluoride, XeF 4 .

For the XeF 4 Lewis structure we first count the valence electrons for the XeF 4 molecule using the periodic table. Once we know how many valence electrons there are in XeF 4 we can distribute them around the central atom and attempt to fill the outer shells of each atom. The Lewis structure for XeF 4 has a total of 36 valence electrons. When we are done adding valence electrons we check each atom to see if it has an octet (full outer shell). We also need to check to make sure we only used the number of available valence electrons we calculated earlier (no more, no less). The Lewis structure for XeF 4 is a bit tougher since you have to take formal charges into account to find the best Lewis structure for the molecule. Remember that Xenon can have more than 8 valence electrons.

The table shows the atomic number and boiling points of some noble gases. Gas helium neon argon krypton xenon Atomic number 2 10 18 36 54 Boiling point / C o - 269 - 246 - 186 - 153 - 107 Xenon forms a number of covalently bonded compounds with fluorine. Suggest a shape for XeF 4 . Explain your answer.

For the XeF 4 Lewis structure we first count the valence electrons for the XeF 4 molecule using the periodic table. Once we know how many valence electrons there are in XeF 4 we can distribute them around the central atom and attempt to fill the outer shells of each atom. The Lewis structure for XeF 4 has a total of 36 valence electrons. When we are done adding valence electrons we check each atom to see if it has an octet (full outer shell). We also need to check to make sure we only used the number of available valence electrons we calculated earlier (no more, no less). The Lewis structure for XeF 4 is a bit tougher since you have to take formal charges into account to find the best Lewis structure for the molecule. Remember that Xenon can have more than 8 valence electrons.

The table shows the atomic number and boiling points of some noble gases. Gas helium neon argon krypton xenon Atomic number 2 10 18 36 54 Boiling point / C o - 269 - 246 - 186 - 153 - 107 The structure of xenon trioxide is shown below. By referring to electron pairs, explain why xenon trioxide has this shape.

XeO3 has pyramidal structure, which may be explained based on the sp3 hybridisation of Xe valence orbitals. As before, the electrons in the p- orbitals get excited into the d- orbitals in the excited state.

The table shows the atomic number and boiling points of some noble gases. Gas helium neon argon krypton xenon Atomic number 2 10 18 36 54 Boiling point / C o - 269 - 246 - 186 - 153 - 107 The structure of xenon trioxide is shown below. Draw the structure of xenon trioxide to show the partial charges on the atoms and the direction of the dipole in the molecule.

The shape of a molecule depends upon the number of valence shell electron pairs (bonded or non-bonded) surrounding the central atom which repel one another and tend to occupy such positions in space which minimise repulsions. The molecular geometry of XeO 3 is trigonal pyramidal with asymmetric charge distribution on the central atom. Dipole moment is a vector quantity and by convention it is depicted by a small arrow with tail on the negative centre and head pointing towards the positive centre. Therefore, this molecule is polar.

EASY

AS and A Level

IMPORTANT

Earn 100

The table shows the atomic number and boiling points of some noble gases.

Gas helium neon argon krypton xenon

Atomic number $2$ $10$ $18$ $36$ $54$

Boiling point / ${}^{o}C$ $- 269$ $- 246$ $- 186$ $- 153$ $- 107$

Use ideas about forces between atoms to explain this trend in boiling points.

Important Questions on Chemical Bonding

EASY

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 1

The table shows the atomic number and boiling points of some noble gases.

Gas	helium	neon	argon	krypton	xenon
Atomic number	$2$	$10$	$18$	$36$	$54$
Boiling point / ${}^{o}C$	$- 269$	$- 246$	$- 186$	$- 153$	$- 107$

Xenon forms a number of covalently bonded compounds with fluorine. Define the terms covalent bond.

EASY

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 1

The table shows the atomic number and boiling points of some noble gases.

Gas	helium	neon	argon	krypton	xenon
Atomic number	$2$	$10$	$18$	$36$	$54$
Boiling point / ${}^{o}C$	$- 269$	$- 246$	$- 186$	$- 153$	$- 107$

Xenon forms a number of covalently bonded compounds with fluorine. Draw a dot-and-cross diagram for xenon tetrafluoride, ${XeF}_{4}$ .

EASY

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 1

The table shows the atomic number and boiling points of some noble gases.

Gas	helium	neon	argon	krypton	xenon
Atomic number	$2$	$10$	$18$	$36$	$54$
Boiling point / ${}^{o}C$	$- 269$	$- 246$	$- 186$	$- 153$	$- 107$

Xenon forms a number of covalently bonded compounds with fluorine. Suggest a shape for ${XeF}_{4}$ . Explain your answer.

EASY

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 1

The table shows the atomic number and boiling points of some noble gases.

Gas	helium	neon	argon	krypton	xenon
Atomic number	$2$	$10$	$18$	$36$	$54$
Boiling point / ${}^{o}C$	$- 269$	$- 246$	$- 186$	$- 153$	$- 107$

The structure of xenon trioxide is shown below.

Question Image

By referring to electron pairs, explain why xenon trioxide has this shape.

EASY

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 1

The table shows the atomic number and boiling points of some noble gases.

Gas	helium	neon	argon	krypton	xenon
Atomic number	$2$	$10$	$18$	$36$	$54$
Boiling point / ${}^{o}C$	$- 269$	$- 246$	$- 186$	$- 153$	$- 107$

The structure of xenon trioxide is shown below.

Question Image

Draw the structure of xenon trioxide to show the partial charges on the atoms and the direction of the dipole in the molecule.

EASY

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 3

Electronegativity values can be used to predict the polarity of bonds. Define the term electronegativity.

HARD

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 5

Methane,

{CH}_{4}

, is a gas at room temperature. Explain why methane is a gas at room temperature.

MEDIUM

AS and A Level

IMPORTANT

Chemistry for Cambridge International AS & A Level Coursebook with Digital Access (2 Years)>Chapter 4 - Chemical Bonding>EXAM-STYLE QUESTIONS>Q 5

Draw a diagram to show the shape of a molecule of methane. On your diagram show a value for the

HCH

bond angle.

The table shows the atomic number and boiling points of some noble gases. Gas helium neon argon krypton xenon Atomic number 2 10 18 36 54 Boiling point / Co -269 -246 -186 -153 -107 Use ideas about forces between atoms to explain this trend in boiling points.

Important Questions on Chemical Bonding

Learn and Prepare for any exam you want !

The table shows the atomic number and boiling points of some noble gases.

Gas helium neon argon krypton xenon

Atomic number $2$ $10$ $18$ $36$ $54$

Boiling point / ${}^{o}C$ $- 269$ $- 246$ $- 186$ $- 153$ $- 107$

Use ideas about forces between atoms to explain this trend in boiling points.