Chemical Bonding

Question 1

what is the difference between intra-molecular bonding and inter-molecular bonding?

Answer 1

intra-moleculae: the way atoms bond
inter-molecular: the way molecule bonds

Question 2

what is the octet rule?

Answer 2

all atoms, when forming compounds, lose, gain or share electrons- to achieve electron configuration of noble gas.
meaning, to have full valence shell and reach stability.

Question 3

why boron (B) special?

Answer 3

needs only 6 electrons in its valence shell to reach stability.

Question 4

ionic compounds

Answer 4

opposing charged ions are attracted to each other by electrostatic forces.

Question 5

what is “ionic lattice”?

Answer 5

the structure formed in ionic componds.
every negativly charged atom surronded by positive charged atoms, and vice versa.
solid in room temp.

Question 6

Metallic Bond

Answer 6

when 2 or more metal atoms in thier elemental state bonds with each other. they share and lose their valence electrons, those electrons become delocalized.

Question 7

what are delocalized electrons?

Answer 7

Electrons that do not belong or attach to a specific atom, and their location is constantly changing.

Question 8

what is “metallic lattice”?

Answer 8

cations are strongly attracted to the delocalized electrons between them.

Question 9

what affects the strength of the metallic lattice?

Answer 9

• number of delocalized electrons (the more the merrier)
• cation charge (more positive, better attraction to the electrons)
  -cation radius (the smaller, the better)

Question 10

what are the properties of the metallic bond?

Answer 10

• high boiling & melting point
  -conduct electricity & heat

Question 11

Covalent Bond

Answer 11

form between two non-metals
based on sharing electrons from the valence shell.
the electrons that are now shared belong to both atoms (giver & receiver)

Question 12

How can we know how many electrons are being shared?

Answer 12

octet rule- the atoms want to reach stability.

Question 13

how many electrons can be shared?

Answer 13

there are 3 types of bonds:
- single bond (one pair of electrons)
- double bond (2 pairs)
- triple bond (3 pairs)

Question 14

what is a “lone pair”?

Answer 14

electrons in the valence shell, who are coupled with others, and cannot be shared in a covalent bond.

Question 15

what is the length of a covalent bond?

Answer 15

the distance between two bonded nuclei

Question 16

what is the strength of a covalent bond?

Answer 16

the amount of energy required to break the bond

Question 17

what affects the covalent bond length?

Answer 17

• size of atoms
• bond order (single>double>triple)
• electronegativity differences between the atoms (polarity).

Question 18

what affects the covalent bond strength?

Answer 18

• bonds of higher order are stronger

Question 19

breaking a double bond vs. single bond

Answer 19

breaking a double bond to form a single bond is easier than breaking a single bond.

Question 20

bond polarity

Answer 20

electrons that are being shared between atoms with different electronegativity values will be more strongly drawn to the more electronegative atom, which forms unequal distribution of electric charge between the atoms.

Question 21

what is a partial charge?

Answer 21

when there is a difference in the electronegativity in a covalent bond, the more electronegativity atom will have constant partial negative charge due to an excess of electrons. the other atom will have constsnt partial positive charge.

Question 22

what is a dipole moment?

Answer 22

an electric dipole describes the creation of partial positive and negative charges on opposite atoms of the bond.
-it has a direction represented by an arrow (points to the negataive end of the dipole)

Question 23

what are the types af covalent bond?

Answer 23

pure: exect same electronegativity values
non-polar: similar electronegativity values
polar bond: different electronegativity values

Question 24

which type of covalent bond is the strongest?

Answer 24

polar bonds

Question 25

what affects the molecule structure?

Answer 25

• amounts of bonds
• number of lone pairs

Question 26

why carbon oxide is non polar?

Answer 26

because of the molecule structure.
the dipole goes to two opposite direction, canceling each other

Question 27

what is a coordinate bond?

Answer 27

electron sharing, in which both electron arrives from the same atom (from the lone pair)

Question 28

what is common to both beryllium, aluminium and d block metals?

Answer 28

all of them are metals and can form covalent bond.

Question 29

what is the lewis structure?

Answer 29

the most common way to draw molecules.
dots= valence electrons
lines= bonds

Question 30

VSEPR theory

Answer 30

Valence Shell Electron Pair Repultion
based on the repulsion relations between electrons.

Question 31

what does the VSEPR theory states?

Answer 31

stabalized orientation will be that in which thr repultion between electrons is minimized–> the electrons will be located as far as possible from each other.