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Flashcards in chem chapter 6 quiz Deck (32):
0

what element is usually the central atom in lewis structure

least electronegative

1

all atoms need 8 electrons, except...

hydrogen needs 2, boron needs 6, beryllium needs 4

2

the number of available electrons is equal to the _____________

number of valence electrons of the atom

3

shared electrons=

N-A (always even)

4

number of bonds=

S/2

5

H is never involved in a multiple bond
___,____ and ___ often form double and triple bonds

C, N, O

6

total number of electrons should equal the ______ number

A

7

what is the metallic trend

increases up to down, right to left

8

what is the atomic radii trend
why

increases up to down(valence electron is occupying higher energy level/n value increases making radius larger), increases right to left (number of protons increases (nuclear charge) pulling the electrons in tighter making the radius smaller

9

the differences in electronegativities is the classifier of bonds, what are the ranges for each

polar covalent 1.7>or equal to x > or equal to .5
pure covalent x<.5
ionic x>1.7

10

isoelectronic means?

same number of electrons

11

what is the atomic radii

distance from the center of the nucleus to the "edge" of the electron cloud
usually measured in picometers or angstroms (1x10^-10m)
must be in gas form
center of nucleus to center of nucleus divided by 2

12

what is the atomic radii trend for cations?
anions?

cations: increases up to down, right to left
anions: increases up to down, left to right

13

when hydrogen becomes an ion, it is just an ____

electron

14

______ do not have ionic radii because they do not form ions

noble gases

15

what is shielding effect

inner electrons shield valence electrons from positive charge of the nucleus (protons) (concert analogy)

16

what is the ionization energy trend

increases down to up, left to right

17

ionization energy is always _____ meaning energy is added to the atom to remove the electron

endothermic

18

how are ionization energy and atomic radius related

inversely proportional

19

what is ionization energy

the energy required to move an electron from an atom is ionization energy

20

the larger the atom is, the (harder/easier) it is for electrons to be removed

easier

21

why does ionization energy increase left to right? down to up?

because atoms towards the right do not want to gain electrons, they want to lose
because the electrons are held in lower-energy orbitals, closer to the nucleus and therefore are more tightly bound (harder to remove).

22

what is the electron affinity trend

increases down to up, left to right

23

what is electron affinity

a measure of the energy change when an electron is added to a neutral atom to form a negative ion

24

what is electron affinity opposite of

ionization energy

25

why does electron affinity increase down to up, left to right

because the electrons added to energy levels become closer to the nucleus, thus a stronger attraction between the nucleus and its electrons

26

what is the electronegativity trend

increases down to up, left to right

27

what is electronegativity

holding onto its own electrons and taking other ones

28

why does electronegativity increase down to up and left to right

This occurs due to a greater charge on the nucleus, causing the electron bonding pairs to be very attracted to atoms placed further right on the periodic table

29

what is the difference between electron affinity and ionization energy

electron affinity is a measure of the energy change when an electron is added while ionization energy is the energy required to remove an electron

30

why does fluorine have a higher ionization energy than iodine?

it has less electrons-lesser shielding/greater attraction between the electrons and the nucleus

31

why do elements in the same family generally have similar properties

they have the same amount of valence electrons