bonding and periodic properties

Question 1

who came up with how elements should be grouped?

Answer 1

dmitri mendeleev and lothar meyer

Question 2

who is mostly credited for organization of the table? why?

Answer 2

mendeleev because he used chemical properties to organize the table and predicted some missing elements

Question 3

what was mendeleev’s table based on

Answer 3

atomic masses

Question 4

about 35 years later who discover the nuclear atom?

Answer 4

ernest rutherford

Question 5

who developed the concept of the atomic number?

Answer 5

henry moseley

Question 6

what is periodicity?

Answer 6

the repetitive pattern of a property for elements based on atomic number

Question 7

Zeff =Z -S

Answer 7

Zeff is effective nuclear charge where Z is the atomic number and S is a screening constant

Question 8

effective nuclear charge

Answer 8

increases across a period and decreases down a group

add e- across, add energy level down

Question 9

what is half of the shortest distance separating two nuclei during collision or atoms

Answer 9

nonbonding atomic radius

van fee Waals radius

Question 10

atomic radius

Answer 10

decreases across period

increases down group

Question 11

cations

Answer 11

smaller than parents, outer most e- removed and repulsion between e- is reduced

Question 12

anion

Answer 12

larger than parent, electron added and repulsion between e- is increased

Question 13

ions have the same number of e-, same electron configuration

Answer 13

isoelectronic series

Question 14

what is ionization energy?

Answer 14

the minimum energy required to remove an electron from the ground state of a gaseous atom or ion

Question 15

the higher the ionization energy

Answer 15

the harder it is to remove an e-

Question 16

ionization energy

Answer 16

increases across

decreases down

Question 17

what is electron affinity?

Answer 17

the energy change accompanying the addition of an e- to a gaseous mixture

Question 18

electron affinity

Answer 18

increases across period
exceptions include 2A, 5A, 8A but it is full-half full
no change in a group

Question 19

electronegativity

Answer 19

increases across

decreases down

Question 20

what is electronegativity?

Answer 20

the ability of an atom in a molecule to attract e- to itself

Question 21

what do metals tend to form

Answer 21

cations

Question 22

what color is the flame of Li? Na? K?

Answer 22

Li pink/red
Na orange
K purple

Question 23

ionic bonding

Answer 23

e- are transferred

Question 24

covalent bonding

Answer 24

e- are shared

Question 25

metallic bonding

Answer 25

happens with metals e- are given to metal

Question 26

lewis dot diagram

Answer 26

dots surrounding atomic symbol to represent valence e-

Question 27

octet rule

Answer 27

says atoms will try to get 8 e- by transferring or sharing e-

Question 28

how do you draw a lewis structure?

Answer 28

add up number of valence e-

put C or N in middle if in compound if not put single atom that isn’t H, add lone pairs if needed

Question 29

when can the octet rule be broken?

Answer 29

group 3A and phosphorus square

Question 30

what is the longest bond?

Answer 30

single

Question 31

which bond is the strongest?

Answer 31

3

Question 32

formal charges

Answer 32

FC= valence - bonded

you want the least amount of charge

Question 33

resonance structures

Answer 33

produced when 2+ structures can be drawn where the only difference is the placement of electrons

Question 34

lone pairs cause what to occur

Answer 34

bond angles to be smaller

Question 35

multiple bonds(2-3) are poked at as

Answer 35

1

Question 36

polar molecule

Answer 36

has an uneven distribution of charge for the entire molecule. this is usually caused by lone pairs of electrons around the central atom

Question 37

dipole moment

Answer 37

exist i don’t a molecule that is polar, shows that there is an uneven distribution of charge

Question 38

single bonds are

Answer 38

sigma bonds

Question 39

multiple bonds are

Answer 39

1 sigma and all others pi

Question 40

molecular orbital theory

Answer 40

was developed to explain some problems that exist with VSEPR and valance bond theories

Question 41

molecular orbitals
bonding orbital favors what?
antibonding orbital favors what?

Answer 41

bonding orbital favors bonding, low in energy

anti bonding orbital favors supérate bonding, high in energy

Question 42

🔺H= E broken- E formed

Answer 42

where 🔺H is enthalpy and E is bond enthalpies