Question

i) Write the condensed electron configurations for the following ions:

(a) Ca+ (b) S2- (c) V2+ (d) Mn3+ (e) Zn2+

ii) Circle the solid in each of the following sets of ionic compounds that have the highest lattice energy.

(a) CaF2, MgF2, SrF2 (b) LiCl, LiF, LiI (c) CaBr2, LiBr, NaBr (d) MgCl2, MgF2, MgO (e) NaF, NaNO3, Na2O

iii) True or false.

(a) Effective nuclear charge (Zeff) is the positive charge experienced by the electron from the nucleus and it

decreases from left to right across the period. Answer: __________

(b) Effective nuclear charge slightly increases going down a group. Answer: __________

(c) Zeff for fluorine is smaller than that of lithium. Answer: __________

(d) Atomic radius tends to increase from top to bottom of a group because of the increase in the magnetic

quantum number. Answer: __________

(e) Anions are larger than their parent atoms because electrons are added to the valence shell increasing the

electron-electron repulsions. Answer: __________

(f) Ca2+ is larger than K+ because K+ has an extra proton. Answer: __________

(g) The ionization energy of K2+ is significantly higher than K+ because it takes more energy to remove the

inner-shell core electron. Answer: __________

(h) Iron, lithium, and sodium are metallic elements because they are on the left side of the periodic table.

Answer: __________

(i) Antimony, argon, and silicon are metalloids that their properties fall between those of metals and those of

nonmetals. Answer: __________

(j) Lattice energy is the energy required to completely separate one mole of solid ionic compound into its

gaseous ions and it is always a positive number. Answer: __________

iv) Calculate the difference in electronegativity and classify the bonding for the following as ionic, covalent,

or polar covalent. Use the electronegativity values from Figure. 8.7.

(a) N-F Answer: Electronegativity difference = ____; ionic/nonpolar covalent/polar covalent bond.

(b) C-H Answer: Electronegativity difference = ____; ionic/nonpolar covalent/polar covalent bond.

(c) Br-Br Answer: Electronegativity difference = ____; ionic/nonpolar covalent/polar covalent bond.

(d) K-Cl Answer: Electronegativity difference = ____; ionic/nonpolar covalent/polar covalent bond.

(e) O-H Answer: Electronegativity difference = ____; ionic/nonpolar covalent/polar covalent bond.

Answer 1

1)

a)

electron configuration for Ca:

1s ²2s ²2p ⁶3s ²3p ⁶4s ²

Ca+ will have 1 electron less.

its electron configuration is:

1s ²2s ²2p ⁶3s ²3p ⁶4s ¹

b)

electron configuration of S:

1s2 2s2 2p6 3s2 3p4

S2- will have 2 electron more

Its electronic configuration will be:

1s2 2s2 2p6 3s2 3p6

c)

Electron configuration of V is:

1S2 2S2 2P6 3S2 3P6 3d³ 4s²

V2+ will lose 2 lectrons:

Its electronic configuration will be:

1S2 2S2 2P6 3S2 3P6 3d³

d)

for Mn3+ it is,

1S2 2S2 2P6 3S2 3P6 3d4

e)

for Zn2+ it is:

1s2 2s2 2p6 3s2 3p6 3d10

I am allowed to answer only 1 question at a time