Answer to Question #101933 in General Chemistry for jude

Question

1. a) Explain the difference between ionic and covalent bonds and use dot and cross diagrams to illustrate and explain ionic, covalent, metallic and dative covalent bonding

b) Which of the following is/are ionic compounds?

Magnesium chloride, water, calcium carbonate, aluminium, carbon dioxide

c) Draw dot and cross diagrams, with outer shells only for:

i) NaCl
ii) MgS
iii) Na2O
iv) Mg3N2

d) Draw dot and cross diagrams, with outer shells only, for:

i) CH4
ii) NH3
iii) H2O
iv) SF6
v) CO2


e) i) Explain how a dative covalent bond differs from a normal covalent bond.

ii) Draw a dot and cross diagram, with outer shells only, for the ammonium (NH4+) ion.

Answer 1

1) a) Covalent bonding occurs when a pair of nuclei share a pair of electrons with one electron being donated by each atom. In dative covalent bonding the same principle of sharing electrons between two nuclei applies except in this case both of the electrons involved in bonding are donated by one of the atoms.

b) Magnesium chloride, water, calcium carbonate and carbo dioxide.

c) Na : Cl.

Mg::S

Na:O:Na

Mg::N:Mg:N::Mg

d) :H

H:C:H

:H

H:

H :N:H

H:O:H

3F:S:3F

O::C::O

e) i) They differ from each other according to the way they form. Therefore, the key difference between covalent bond and dative bond is that a covalent bond forms when unpaired electrons of two atoms associate with each other whereas dative bond form when an atom donates one of its electron pairs to another atom.

ii) H3:N(H+)