Periodicity, Charge,Chapter 7.1-7.8 Flashcards Preview

CHE 106 > Periodicity, Charge,Chapter 7.1-7.8 > Flashcards

Flashcards in Periodicity, Charge,Chapter 7.1-7.8 Deck (24):
1

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

right DEcreses , down INcreses

2

Atomic radius tends to depend on 2 factors:

principal quantum number, n.
effective nuclear charge (Zeff)

3

(Zeff), equation

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

4

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

2s, 2p

5

bonding atomic radius is

one-half of the distance between covalently bonded nuclei.

6

what is bond order

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

7

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

shorter,higher

8

Ionic size depends upon:

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

9

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

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

10

Anions (-) are _____than their parent atoms

larger Electrons are added and repulsions between electrons are increased.

11

Ions _____ in size as you go down a column.
This is due to

increase, increasing value of n

12

an isoelectronic series,

ions have the same number of electrons.

13

effective nuclear charge

strength of the pull the electron fells from the nucleus

14

first ionization energy is the minimal energy needed to

remove electron from the neutral atom.

15

how is ionization energies related to size

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

16

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

right increases down decreases

17

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

in B one electron is father away fron the nucleus

18

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

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

19

It requires_____ energy to remove successive electrons.
When all valence electrons have been removed, the ionization energy...

more, increases drasticaly

20

electron affinity is the energy change for the process

of adding an electron to a neutral atom in the .

21

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

right increases down decreases

22

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

exothermic, left to right

23

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

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

24

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

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