10/16 notes

Question 1

is CaCO3 brittle or maleable

Answer 1

brittle because it is an ionic compound

Question 2

what are covalent compounds

Answer 2

non metals + non metals

Question 3

if only non metals are involved, what is the ionization energy

Answer 3

ionization energies are high, so it is unfavorable to lose (and therefore transfer) electrons

Question 4

bohr model solution

Answer 4

share electrons by overlapping valence shell to achieve noble gas configuration

Question 5

orbital view of covalent bond

Answer 5

overlap one-electron orbitals -> forms covalent bonds

The strength of a covalent bond is proportional to the amount of overlap between atomic orbitals; that is, the greater the overlap, the more stable the bond.

Question 6

what tells us if the covalent bond is stable

Answer 6

wave functions

Question 7

properties of bonding molecular orbital

Answer 7

1)constructive interference
2)add waves
3)energetically favorable
4)puts electron density in the bond region between the nuclei

Question 8

what causes repulsion

Answer 8

pauli exclusion principle

Question 9

anti-bonding molecular orbital properties

Answer 9

1)destructive interference
2)has a node
3)energetically unfavorable
4)because of node: zero probability of finding the electron

Question 10

what makes a polar covalent bond

Answer 10

electrons pair is unequally shared. One element is more electronegative than the other, pulls electron density towards itself, and starts to acquire a negative electronegative charge. The other atom acquires positive electronegative charge as its electrons are being pulled away

Question 11

how are electrons shared in nonpolar covalent bond

Answer 11

equally

Question 12

what is electonegayvity

Answer 12

the ability to attract shared electrons in a chemical bond

Question 13

what is electron affinity

Answer 13

the energy change from gaining an electron

Question 14

how does electronegativity change according to the periodic table

Answer 14

increases as you go up periodic table and increases as you go right across periodic table.

Question 15

what element is most electronegative

Answer 15

flourine

Question 16

more polar bonds have larger ________ in _______ between 2 elements

Answer 16

differences; electronegativity

Question 17

polar bonds have _______ _________ ________ that strengthens bonds

Answer 17

additional electrostatic attraction

Question 18

what is polarizability

Answer 18

how ‘free’ valence electrons are to move away from the nucleus

Question 19

effective nuclear charge and polarizability for high EN elements

Answer 19

have large effective nuclear charge and low polarizability

Question 20

nuclear charge and polarizability for low EN elements

Answer 20

smaller effective nuclear charge and higher polarizability

Question 21

why dont non metals transfer electrons like ionic bonds

Answer 21

Because they have low electronegative differences. Non metals also cant transfer electrons as quickly

Question 22

according to the octet rule

Answer 22

Atoms will tend to lose, gain, or share electrons such that their valence electrons shell resembles that of a noble gas

Question 23

what is octet rule

Answer 23

an atom will be most stable when surrounded by 8 electrons in a valence shell. An atom with 8 electrons will bond with an atom that does not.

Question 24

According to orbital overlap concept

Answer 24

the formation of a covalent bond between two atoms results by the pairing of electrons present in the valence shell having opposite spins.

Question 25

why are noble gases not assigned electronegativity values

Answer 25

Since noble gases already have a full valence shell of electrons and are stable, they have no need for attracting electrons so no, they do not have electronegativity.

Question 26

what is polarity

Answer 26

when an entity contains two distinct and opposite poles that can either attract or repel each other

Question 27

How does electronegativity help us rank how polar a bond is?

Answer 27

The greater the difference in electronegativity, the more polarized the electron distribution and the larger the partial charges of the atoms.

Question 28

In the Periodic Table, which atoms are more polarizable, which are less polarizable, and why?

Answer 28

polarizability decreases from left to right, but increases down on columns of the periodic table. Larger molecules are generally more polarizable than smaller ones.

Question 29

what is least electronegative element

Answer 29

cesium