bonding

Question 1

what is the definition of ionic bonding?

Answer 1

Ionic bonding is the electrostatic force of attraction between oppositely charged ions formed by electron transfer.

Question 2

what is the definition of covalent bond?

Answer 2

share pair of electrons

Question 3

what is dative covalent bond?

Answer 3

A dative covalent bond forms when the
shared pair of electrons in the covalent bond
come from only one of the bonding atoms. A
dative covalent bond is also called co-ordinate
bonding.

Question 4

what is metallic bonding?

Answer 4

electrostatic force of attraction between the
positive metal ions and the delocalised electrons

Question 5

what are the 3 main factors that affect the strength of metallic bonding?

Answer 5

1. Number of protons/ Strength of nuclear attraction.
   The more protons the stronger the bond
2. Number of delocalised electrons per atom (the outer shell electrons are delocalised)
   The more delocalised electrons the stronger the bond
3. Size of ion.
   The smaller the ion, the stronger the bond.

Question 6

what are some examples of simple molecular (gases and liquids) compounds?

Answer 6

Iodine
Ice
Carbon dioxide
Water
Methane

Question 7

what are some examples of macromolecular (solid) compounds?

Answer 7

Diamond
Graphite
Silicon dioxide
Silicon

Question 8

when can you only talk about molecules and intermolecular forces?

Answer 8

when talking about simple molecular substances

Question 9

how are metals malleable?

Answer 9

Malleable as the positive ions in the lattice are all identical. So the planes of ions can slide easily over one another

Question 10

describe a linear shape

Answer 10

• 2 bonding pairs
• 0 lone pairs
• bond angle is 180
  or
• 2 bond pairs
• 3 lone pairs

Question 11

describe trigonal planar

Answer 11

• 3 bonding pairs
• 0 lone pairs
• bond angle 120

Question 12

describe tetrahedral

Answer 12

• 4 bonding pairs
• 0 lone pairs
• bond angle 109.5

Question 13

describe trigonal pyramidal

Answer 13

• 3 bonding pairs
• 1 lone pair
• bond angle 107

Question 14

describe bent

Answer 14

• 2 bonding pairs
• 2 lone pairs
• bond angle 104.5

Question 15

describe trigonal bipyramidal

Answer 15

• 5 bonding pairs
• 0 lone pairs
• 120/90

Question 16

describe octahedral

Answer 16

• 6 bonding pairs
• 0 lone pairs
• bond angle 90

Question 17

describe square pyramidal

Answer 17

• 5 bonding pair
• 1 lone pair
• bond angle 90

Question 18

describe square planar

Answer 18

• 4 bond angle
• 2 lone pair
• bond angle 90

Question 19

describe T shape

Answer 19

• 3 bonding angle
• 2 lone pair
• bond angle 87.5

Question 20

describe seesaw

Answer 20

• 4 bond angles
• 1 lone pair
• bond angle 86.5/102

Question 21

how to explain shape of molecule

Answer 21

State number of bonding pairs and lone pairs of electrons.
2. State that electron pairs repel and try to get as far apart as possible (or to a position of minimum repulsion.)
3. If there are no lone pairs state that the electron pairs repel equally
4. If there are lone pairs of electrons, then state that lone pairs repel more than bonding pairs.
5. State actual shape and bond angle

Question 22

What is electronegativity?

Answer 22

Electronegativity is the relative tendency of an atom in a covalent bond to attract electrons in a covalent bond to itself.

Electronegativity is a key concept in understanding how atoms interact in molecules.

Question 23

Which atoms are the most electronegative?

Answer 23

F, O, N, and Cl

These elements have a strong tendency to attract electrons.

Question 24

On which scale is electronegativity measured?

Answer 24

Pauling scale

The Pauling scale ranges from 0 to 4.

Question 25

What is the electronegativity value of fluorine?

Answer 25

4.0 ## Footnote Fluorine is the most electronegative element.

Question 26

What happens to electronegativity across a period?

Answer 26

Electronegativity increases ## Footnote This is due to an increase in the number of protons and a decrease in atomic radius.

Question 27

What happens to electronegativity down a group?

Answer 27

Electronegativity decreases ## Footnote This is caused by increased distance between the nucleus and outer electrons, along with increased shielding.

Question 28

What types of bonding exist on the continuum of bonding types?

Answer 28

Ionic and covalent bonding ## Footnote These represent the extremes of bonding types based on electronegativity differences.

Question 29

What characterizes a purely covalent compound?

Answer 29

Elements of similar electronegativity ## Footnote A small electronegativity difference indicates a purely covalent bond.

Question 30

What characterizes an ionic compound?

Answer 30

Elements of very different electronegativities (> 1.7) ## Footnote A large electronegativity difference results in ionic bonding.

Question 31

What is a polar covalent bond?

Answer 31

A bond formed when elements have different electronegativities (0.3 to 1.7) ## Footnote This results in a permanent dipole.

Question 32

In a polar covalent bond, which element has the δ- end?

Answer 32

The element with larger electronegativity ## Footnote This creates a dipole moment in the molecule.

Question 33

What produces a charge separation in a molecule?

Answer 33

Electrons in the bond ## Footnote This results in a dipole with positive and negative ends.

Question 34

What defines a polar molecule?

Answer 34

A molecule with a net dipole moment due to charge separation.

Question 35

What defines a non-polar molecule?

Answer 35

A molecule with no net dipole moment, often due to symmetry.

Question 36

What happens to individual dipoles in a symmetric molecule?

Answer 36

They cancel out due to the symmetrical shape.

Question 37

What is an example of a non-polar molecule?

Answer 37

CCI ## Footnote This molecule is symmetrical and has identical bonds.

Question 38

What is an example of a polar molecule?

Answer 38

CH Cl ## Footnote This molecule has a net dipole moment.

Question 39

What determines if a symmetric molecule is polar or non-polar?

Answer 39

The symmetry and identical bonds.

Question 40

Fill in the blank: A symmetrical molecule will not be polar even if individual bonds within the molecule are _______.

Answer 40

polar

Question 41

True or False: A symmetric molecule can have a net dipole moment.

Answer 41

False

Question 42

What is the significance of a net dipole moment in determining molecular polarity?

Answer 42

It indicates whether the molecule is polar or non-polar.

Question 43

how do VDW arise between molecules

Answer 43

- random movement of electrons in a molecule creates a dipole - induced dipole in a neighbouring molecule - these temporary dipoles attract between delta positive and delta negative

Question 44

what are permanent dipole-dipole forces

Answer 44

*Permanent dipole-dipole forces occurs between polar molecules *They are stronger than Van der Waals and so the compounds have higher boiling points *Polar molecules are asymmetrical and have a bond where there is a significant difference in electronegativity between the atoms.

Question 45

what is hydrogen bonding

Answer 45

-It occurs in compounds that have a hydrogen atom attached to one of the three most electronegative atoms of nitrogen, oxygen and fluorine, which must have an available lone pair of electrons. -strongest bond