3 Chem Bonding

Question 1

Chemical bonds

Answer 1

Electrostatic forces of attraction that exist within particles

Question 2

Electronegativity

Answer 2

Measure of its ability to attract electrons in a bond

Question 3

Metallic bonds

Answer 3

Strong electrostatic forces of attraction between lattice of cations and “sea” of delocalized valence electrons

Question 4

Factors affecting metallic bonds

Answer 4

1. Charge of ion/size of ion
2. Number of valence electrons

Question 5

Ionic bonds

Answer 5

strong electrostatic forces of attraction between positively charged cations and negatively charged anions

Question 6

Coordination number

Answer 6

number of oppositely charged ions surrounding an ion

Question 7

Magnitude of lattice energy

Answer 7

proportional to abs(product of charge/summation of radius)

Question 8

Covalent bonds

Answer 8

Strong electrostatic forces of attraction between the nuclei of each atom for the shared pair of electrons

Question 9

Expansion of octet

Answer 9

Presence of vacant energetically accessible d orbitals (occurs for elements in Period 3 and higher)

Question 10

Sigma bond

Answer 10

When orbitals overlap head-on/collinearly resulting in a concentration of the electron density between the nuclei of bonding atoms

Question 11

Pi bond

Answer 11

When two p orbitals overlap sideways/collaterally, resulting in a concentration of the electron density above and below the internuclear axis.

Question 12

Co-ordinate (dative) bonds

Answer 12

When an atom donates a lone pair of electrons into an empty orbital of an electron deficient atom

Question 13

Factor affecting covalent bonds

Answer 13

1. Effectiveness of orbitals (larger size of atom, more diffused valence orbitals, less effective overlap)
2. Bond mulplicity (single bond<double bond<triple bond)
3. Polarity of bond

Question 14

Polar covalent bonds

Answer 14

When atoms contributing electrons to the covalent bond have a difference in electronegativities.

Question 15

Valence Shell Electron Pair Repulsion (VSEPR) Theory

Answer 15

1. Electron pairs are arranged as far apart as possible to minimize repulsion
2. Strength of repulsion: lone pair-lone pair>bond pair-lone pair>bond pair-bond pair

Question 16

Dipole

Answer 16

The distribution of charge between two covalently bonded atoms of different electronegativities

Question 17

Permanent dipole-permanent dipole interactions

Answer 17

Weak electrostatic forces of attraction that occurs between polar molecules

Question 18

Instantaneous dipole-induced dipole interactions

Answer 18

Weak electrostatic forces of attraction that occurs between non-polar molecules

Question 19

Hydrogen bonds

Answer 19

Weak electrostatic force of attraction between protonic hydrogen of one molecule and a lone pair on a highly electronegative atoms of another molecules.

Question 20

Bond angle of CH4

Answer 20

109.5°

Question 21

Bond angle of NH3

Answer 21

107°

Question 22

Bond angle of H2O

Answer 22

104.5°