Atoms, Electrons & Chemical Bonding

Question 1

Atomic Number

Answer 1

Number of protons in the nucleus

Question 2

Mass number

Answer 2

Sum of protons + neutrons in the nucleus

Question 3

Isotopes

Answer 3

Same number of protons, different number of neutrons

Question 4

How was wave particle duality discovered?

Answer 4

Schrodinger combined the idea that an electron has wave properties with classical equations of wave motion to give a wave equation for the energy of an electron in an atom

Question 5

What does wave equation give?

Answer 5

A series of solutions called wave functions

Question 6

Quantum numbers

Answer 6

A whole number which specifies the shell and is related to the energy of the orbital

Question 7

Angular Momentum Quantum Number

Answer 7

Usually designed by a letter (s,p,d,f) and describes the shape of the orbital

Question 8

Nodal surface

Answer 8

A region where the probability of finding an electron is zero

Question 9

What do s orbitals increase with?

Answer 9

The number of nodal surfaces

Question 10

Pauli Exclusion Principle

Answer 10

No 2 electrons in the same atom can have the same set of 4 quantum numbers

Question 11

Shape of p orbitals

Answer 11

Dumbells

Question 12

When do p orbitals become possible?

Answer 12

When the quantum number, n = 2 and higher

Question 13

What is an ionic bond formed between?

Answer 13

Metals and nonmetals with very different electronegativity

Question 14

Properties of Ionic bonds

Answer 14

Conductors and have high melting points

Question 15

Electronegativity

Answer 15

The measure of the ability of an atom to attract a pair of electrons

Question 16

How does electronegativity differ across the periodic table?

Answer 16

Increases across the period

Decreases down the group

Question 17

Most electronegative element

Answer 17

Fluorine

Question 18

Least electronegative element

Answer 18

Francium

Question 19

What are covalent bonds formed between?

Answer 19

nonmetallic elements of similar electronegativity

Question 20

Bonds in all polyatomic ions and diatomics

Answer 20

Covalent bonds

Question 21

What draws atoms closer together in covalent bonds?

Answer 21

The mixing of energy sublevels

Question 22

Bond energy

Answer 22

The energy required to break a covalent bond, which is the same as the amount of energy released when the bond is formed

Question 23

Non-polar covalent bonds

Answer 23

When electrons are shared equally

Question 24

Polar Covalent bond

Answer 24

When electrons are shared but unequally

Question 25

Properties of Metals

Answer 25

Good conductors, lustrous, high melting points

Question 26

Octet rule

Answer 26

The tendency for atoms to seek 8 electrons in their outer shell

Question 27

Electron Dot Formulas

Answer 27

The number of dots around each atom is equal to the number of valence electrons the atom has

Question 28

When does a sigma bond occur?

Answer 28

When the bonding orbitals point along the axis connecting the two bonding nuclei

Question 29

When does a pi bond occur?

Answer 29

When the bonding orbitals are parallel to each other and perpendicular to the axis connecting the two bonding nuclei

Question 30

Why are sigma bonds stronger than pi bonds?

Answer 30

The interaction between parallel orbitals is not as strong between orbitals that point at each other

Question 31

Resonance

Answer 31

The two shared electron pairs consitute a double bond

Question 32

Resonance

Answer 32

The two shared electron pairs consitute a double bond