Periodicity, Charge,Chapter 7.1-7.8

Question 1

general trend for atomic radius: as you go right AR _____ as you go down AR _____

Answer 1

right DEcreses , down INcreses

Question 2

Atomic radius tends to depend on 2 factors:

Answer 2

principal quantum number, n.

effective nuclear charge (Zeff)

Question 3

(Zeff), equation

Answer 3

Zeff = Z − S

where Z is the atomic number and S is a shielding constant, usually close to the number of inner electrons.

Question 4

The effective nuclear charge experienced by the __ electron is greater than __ that for the electron.

Answer 4

2s, 2p

Question 5

bonding atomic radius is

Answer 5

one-half of the distance between covalently bonded nuclei.

Question 6

what is bond order

Answer 6

single bond=bond order of 1, double bond =bond order of 2 ect

Question 7

the higher the bond order the _____ the bond length the _____the bond dissociation energy

Answer 7

shorter,higher

Question 8

Ionic size depends upon:

Answer 8

The nuclear charge.
The number of electrons.
The orbitals in which electrons reside.

Question 9

Cations (+) are ____ than their parent atoms. b/c

Answer 9

smaller The outermost electron is removed and repulsions between electrons are reduced.

Question 10

Anions (-) are _____than their parent atoms

Answer 10

larger Electrons are added and repulsions between electrons are increased.

Question 11

Ions _____ in size as you go down a column.

This is due to

Answer 11

increase, increasing value of n

Question 12

an isoelectronic series,

Answer 12

ions have the same number of electrons.

Question 13

effective nuclear charge

Answer 13

strength of the pull the electron fells from the nucleus

Question 14

first ionization energy is the minimal energy needed to

Answer 14

remove electron from the neutral atom.

Question 15

how is ionization energies related to size

Answer 15

it is more difficult to remove an electron that is closer to the nucleus.

Question 16

general trend for ionization energies: as you go right IR_____ as you go down IR

Answer 16

right increases down decreases

Question 17

why is there an exception for IR in Group 2a and 3a Be and B

Answer 17

in B one electron is father away fron the nucleus

Question 18

why is there an exception for IR in Group 5a and 6a , N and O

Answer 18

In N the outer electrons are unpaired so harder to remove them b/c there is less repulsion

Question 19

It requires_____ energy to remove successive electrons.

When all valence electrons have been removed, the ionization energy…

Answer 19

more, increases drasticaly

Question 20

electron affinity is the energy change for the process

Answer 20

of adding an electron to a neutral atom in the .

Question 21

general trend for Electron Affinity: as you go right EA_____ as you go down EA

Answer 21

right increases down decreases

Question 22

In general, electron affinity becomes more_______ as you go from__ to ___ across a row

Answer 22

exothermic, left to right

Question 23

why is there an exception for EA in Groups 4A and 5A. C and N

Answer 23

5a (N) has no empty orbitals to there is more repulsion

Question 24

why is there an exception for EA Groups 1A and 2A Li and Be

Answer 24

In 2a Be added electron must go in a p-orbital, not an s-orbital.which farther from nucleus and feels repulsion