Chemical Bonding

Question 1

A compound is…

Answer 1

a substance that is made up of 2 or more elements chemically combined

Question 2

Octet rule

Answer 2

When bonding occurs, electrons tend to reach an electron arrangement with eight electrons in outer shell

Question 3

Ionic bond

Answer 3

is the force of attraction between oppositely charged ions in a compound

Question 4

A transition metal

Answer 4

Is one that forms at least one ion with a partially filled d-sublevel

Question 5

A covalent bond

Answer 5

is one that involves the sharing of electrons

Question 6

The valency of an element

Answer 6

The number of atoms of hydrogen or an other monovalent element with which each atom of the element combines

Question 7

VSEPR theory

Answer 7

STATES: the shape of a molecule depends on the number of pairs of electrons in the valence shell of the central atom. Since electrons are negatively charged, the electron pairs repel each other and arrange themselves in space so as to be as far away as possible.

Question 8

Electronegativity

Answer 8

the relative attraction an atom in a molecule has for the shared pair of electrons in a covalent bond

Question 9

electronegativity difference greater than 1.7

Answer 9

ionic E.g NaCl= Na(3.16)-Cl(0.93) = 2.23

Question 10

electronegativity difference less than 1.7

Answer 10

covalent E.g H2O= O(3.44)-H(2.2)= 1.24

Question 11

Polar bond

Answer 11

is a covalent bond in which the electrons are shared unevenly (electronegativity difference between 1.7 and 0.4 not inclusive)

Question 12

A dipole

Answer 12

is a pair of electronic charges of equal magnitude but opposite sign, separated by some (usually small) distance

Question 13

ionic bonds usually happen between

Answer 13

metal+ non metal

Question 14

covalent bonds usually happen between

Answer 14

2 non-metals

Question 15

3 types of intermolecular bonding

Answer 15

Van der Waals forces (weakest)
Dipole-Dipole forces
Hydrogen bonds (Strongest)

Question 16

Van der Waals forces are…

Answer 16

weak attractive forces between molecules resulting from the formation of temporary dipoles

Question 17

Dipole-Dipole forces are…

Answer 17

forces of attraction between the negative pole of one and the positive pole of another

Question 18

Hydrogen binds are…

Answer 18

particular types of dipole dipole attractions between molecules in which hydrogen atoms are bonded to nitrogen, oxygen or fluorine. The hydrogen atom carried a partial positive charge and is attracted to the electronegative atom in another molecule. Thus, the hydrogen bond acts as a bridge between two electronegative atoms in seperate molecules