chem chapter 6 test

Question 0

what is electron affinity

Answer 0

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

Question 1

what element is usually the central atom in lewis structure

Answer 1

whichever one is written first (except hydrogen will never be central)

Question 2

what is the electron affinity trend

Answer 2

increases down to up, left to right

Question 3

what is the atomic radii trend for cations?

anions?

Answer 3

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

Question 4

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

Answer 4

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).

Question 5

shared electrons=

Answer 5

N-A (always even)

Question 6

what is the difference between electron affinity and ionization energy

Answer 6

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

Question 7

what is electron affinity opposite of

Answer 7

ionization energy

Question 8

what is ionization energy

Answer 8

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

Question 9

why does fluorine have a higher ionization energy than iodine?

Answer 9

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

Question 10

all atoms need 8 electrons, except…

Answer 10

hydrogen needs 2, boron needs 6, beryllium needs 4

Question 11

why does electronegativity increase down to up and left to right

Answer 11

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

Question 12

what is the electronegativity trend

Answer 12

increases down to up, left to right

Question 13

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

Answer 13

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

Question 14

what is the atomic radii trend

why

Answer 14

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

Question 15

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

Answer 15

easier

Question 16

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

Answer 16

endothermic

Question 17

H is never involved in a multiple bond

___,____ and ___ often form double and triple bonds

Answer 17

C, N, O

Question 18

total number of electrons should equal the ______ number

Answer 18

A

Question 19

isoelectronic means?

Answer 19

same number of electrons

Question 20

how are ionization energy and atomic radius related

Answer 20

inversely proportional

Question 21

what is the atomic radii

Answer 21

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

Question 22

what is shielding effect

Answer 22

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

Question 23

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

Answer 23

noble gases

Question 24

when hydrogen becomes an ion, it is just an ____

Answer 24

electron

Question 25

number of bonds=

Answer 25

S/2

Question 26

why do elements in the same family generally have similar properties

Answer 26

they have the same amount of valence electrons

Question 27

what is electronegativity

Answer 27

holding onto its own electrons and taking other ones

Question 28

what is the metallic trend

Answer 28

increases up to down, right to left

Question 29

the number of available electrons is equal to the _____________

Answer 29

number of valence electrons of the atom

Question 30

what is the ionization energy trend

Answer 30

increases down to up, left to right

Question 31

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

Answer 31

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

Question 32

covalent bonds are the _____ of electrons between two ________, one cation and one anion

Answer 32

sharing, nonmetals

Question 33

if a molecule has 4 total electron domains | what will it look like with 0,1,2,3 lone pairs on the central atom

Answer 33

tetrahedral, trigonal pyramidal, bent, ---

Question 34

of hybrid orbitals formed= what

Answer 34

of domains on the central atom

Question 35

3 electron domains means _____ electron geometry and _____ bond angles

Answer 35

trigonal planar 120

Question 36

equal sharing in covalent bonds means ____ | unequal sharing means _____

Answer 36

nonpolar (do not have opposite ends), polar

Question 37

if a molecule has 2 total electron domains | what will it look like with 0,1,2,3 lone pairs on the central atom

Answer 37

linear----

Question 38

what is bond polarity determined by

Answer 38

electronegativity difference in the bond (dipole)

Question 39

double bonds only exist in ___

Answer 39

planes

Question 40

2 electron domains means _____ electron geometry and _____ bond angles

Answer 40

linear, 180

Question 41

how can you tell if a bond is polar

Answer 41

polar bonds have at least one of these two characteristics one or more lone pairs on center atom (dipoles will angle) if you have different atoms connected to your center (different electronegativities)

Question 42

4 electron domains means _____ electron geometry and _____ bond angles

Answer 42

tetrahedral, 109.5

Question 43

has a magnitude has a value has a direction ex) velocity

Answer 43

vector

Question 44

if a molecule has 6 total electron domains | what will it look like with 0,1,2,3 lone pairs on the central atom

Answer 44

octahedral, square pyramidal, square planar, T-shaped

Question 45

6 electron domains means _____ electron geometry and _____ bond angles

Answer 45

octahedral 180/90

Question 46

if dipoles cancel, you have a ______ bond | how do dipoles cancel

Answer 46

nonpolar | same magnitude, towards or away from each other

Question 47

ionic bonds are a ____ of electrons between a ______ (which loses electrons and becomes a _____) and a _________ (which gains electrons and becomes a _______)

Answer 47

transfer, metal, cation, nonmetal, anion

Question 48

5 electron domains means _____ electron geometry and _____ bond angles

Answer 48

trigonal bipyramidal 180/120/90

Question 49

if a molecule has 5 total electron domains | what will it look like with 0,1,2,3 lone pairs on the central atom

Answer 49

trigonal bipyramdial, see-saw, T-shaped, linear

Question 50

how is molecule polarity determined

Answer 50

whether the dipoles cancel or if there is a resultant

Question 51

how do you indicate if a bond is ionic, polar, or nonpolar

Answer 51

ionic- >1.7 polar- .5-1.7 nonpolar- 0-.4

Question 52

if a molecule has 3 total electron domains | what will it look like with 0,1,2,3 lone pairs on the central atom

Answer 52

trigonal planar, bent, linear,--

Question 53

what is the dipole?

Answer 53

electronegativity inbalance, represented by arrows drawn towards more electronegative element where electrons are found within the bond

Question 54

explain AXE notation

Answer 54

A-central atom X- atoms bonded to central atom E- lone pairs on central atom only example) PF5's notation would be AX5

Question 55

lone pairs on the central atom will result in a bond angle that is ____________ ideal

Answer 55

less than

Question 56

electrostatic attractive force between the partially positive charged hydrogen end of an O-H, N-H, or F-H bond and the negative charge of a lone pair on an O, F, or N

Answer 56

hydrogen bonding

Question 57

electrostatic attractive force between any two molecules

Answer 57

london dispersion force

Question 58

electrostatic attractive force between two polar molecules

Answer 58

dipole-dipole

Question 59

molecules with an indicated charge on in ____ with the charge drawn on the ___

Answer 59

brackets, outside

Question 60

what is the more polar of the following two bonds with the indicated electronegativity inbalance B--->F (2.0) B--->I (0.5)

Answer 60

B--->I because B--->F(2.0) is ionic

Question 61

choose the orbital in which an electron would experience the highest effective nuclear charge (least shielded) and the highest ionization energy Na (3s) Mg (3s) Al (3p) P (3p) S (3p)

Answer 61

Mg (3s) | closest to the nucleus

Question 62

atoms are ____ stable alone than combined with other atoms | why

Answer 62

less | they have to use energy to combine therefore become more stable

Question 63

bond polarity refers to the equal (___) or unequal (___) sharing of electrons molecular polarity refers to the symmetry(___) or asymmetry(___) of a molecule

Answer 63

nonpolar, polar, nonpolar, polar

Question 64

what makes a bond polar (covalent) | if the bond occurs between two ___ nonmetals

Answer 64

different

Question 65

what makes a molecule asymmetrical? | if there are ____________ around the central atom and/or if the surrounding atoms are different ______

Answer 65

lone pairs, elements

Question 66

``` smallest unit formula unit exists as solids, usually crystal shapes have high melting points most dissolve in water melted or dissolved in water conduct electricity fixed + and - parts; anions and cations examples KCL, NaF, KNO3 ```

Answer 66

ionic compounds

Question 67

smallest unit molecule exists as liquids, gases, or non-crystal solids have low melting points few dissolve in water melted or dissolved in water does not conduct electricity may have slightly + and - parts or totally neutral examples NH3, CO2, CH4

Answer 67

covalent (molecular) compounds

Question 68

ionic compounds minimize PE by organizing into _____

Answer 68

crystals