Topic 4: Bonding

Question 1

Positive and negative ions are known respectively as…

Answer 1

Cations and anions

Question 2

Ionic bonding is only between what types of elements?

Answer 2

A bond between a metal and nonmetal

Question 3

What formation and charge does the electrostatic attraction of an ionic bond create?

Answer 3

Neutral lattice

Question 4

Ionic charge corresponds to…

Answer 4

Group number

Question 5

Why does the lattice form in an ionic bond?

Answer 5

Opposite charges hold the ions together, so each ion is surrounded by six other ions with the opposite charge

Question 6

What is the most stable arrangement in an ionic lattice?

Answer 6

Cation and anions are as close as possible to maximize attraction while minimizing repulsion

Question 7

Under normal conditions, ionic compounds are usually in what state and what structure?

Answer 7

Solid, lattice

Question 8

Lattice structures can explain…

Answer 8

ionic compounds’ physical properties

Question 9

What are four specific physical properties of ionic compounds?

Answer 9

Volatility, melting point, electrical conductivity, solubility

Question 10

What is volatility? What is the typical volatility of an ionic compound?

Answer 10

The tendency of a substance to vaporize. Ionic compounds are non volatile due to strong bonds, so room temp. cannot break them

Question 11

What is the melting point for most ionic compounds generally?

Answer 11

High, due to strong bonds and the fact that they are solid at room temp

Question 12

How conductive are ionic compounds?

Answer 12

As solids, not conductive. However, melted ionic compounds and aqueous ionic solutions are conductive because the ions are free to move

Question 13

What is the solubility for ionic compounds?

Answer 13

Soluble in polar solvents, but some are insoluble

Question 14

What is a giant covalent structure? What are some of its properties?

Answer 14

A covalent molecule w/ many nonmetal atoms. Usually giant regular lattices, very strong due to many bonds, high melting point, vary in conductivity

Question 15

What are simple covalent structures? What state is it usually found in?

Answer 15

Only a few atoms held together by strong covalent bonds. Usually liquid or gases due to weak intermolecular forces

Question 16

Covalent bonds are formed through____, usually between_____ and ____ atoms

Answer 16

sharing e-, nonmetal-nonmetal atoms

Question 17

What are some exceptions to the octet rule?

Answer 17

Beryllium and Boron, as well as period 3 elements

Question 18

What is molecular geometry?

Answer 18

Arrangement of atoms in space, position of e- in outer shell for the least repulsion

Question 19

what does the number of electron domains in a covalent molecule determine?

Answer 19

The shape of the molecule due to repulsion

Question 20

What are the three types of electron domain repulsion in order of least to greatest?

Answer 20

bonding pair-bonding < lone-bonding< lone-lone

Question 21

What does VSEPR theory state and stand for?

Answer 21

Valence shell electron pair repulsion. Means that each atom will arrange itself in a covalent bond to minimize repulsion between domains.

Question 22

What are the four steps to drawing a lewis diagram of a covalent molecule, including its bonds?

Answer 22

Sketch lewis diagram of each atom. Find total number of valence e-, and form single bonds between atoms. Each single bond subtracts 2e-. Then w/ remaining e-, add them to the outer atoms to achieve octet. W/ more leftover e-, add them to central atom or arrange them to form double/triple bonds until all atoms have an octet

Question 23

What are the two conditions for a polar molecule?

Answer 23

Must have polar bonds and an asymmetrical distribution of partial charges across the molecule

Question 24

What are four allotropes of carbon?

Answer 24

Diamond, graphite, C60 fullurenes, graphene

Question 25

What are properties of graphite?

Answer 25

Hexagonal structure, weak van der waals forces between layers allow bonds to break easily as layers slide. Strong covalent bonds within layers but not between layers. Covalent layer lattice. Good conductivity due to delocalized e-.

Question 26

What are properties of diamond?

Answer 26

Giant covalent structure, tetrahedral, no weak links, strong bonds, high melting point, poor conductivity bc no delocalized e-

Question 27

What are properties of C60 fullurenes?

Answer 27

60 carbon atoms form a sphere w/ each atom covalently bonded, not a lattice. Strong, light semiconductor used in medicine to transport drugs in the body.

Question 28

What is graphene, and what are its properties?

Answer 28

Hexagonally bonded allotrope of carbon that is one-atom thick. Very strong, light

Question 29

What is the name of a molecule w/ 2 e- domains and no lone pairs? Bond angle?

Answer 29

linear, 180

Question 30

What is the name of a molecule w/ 3 e- domains and no lone pairs? Bond angle?

Answer 30

Trigonal planar, 120

Question 31

What is the name of a molecule w/ 3 e- domains including 1 lone pair? Bond angle?

Answer 31

Bent, <120

Question 32

What is the name of a molecule w/ 4 e- domains and no lone pairs? Bond angle?

Answer 32

Tetrahedral, 109.5

Question 33

What is the name of a molecule w/ 4 e- domains including 1 lone pair? Bond angle?

Answer 33

Trigonal bipyramidal, <109.5

Question 34

What is the name of a molecule w/ 4 e- domains including 2 lone pairs? Bond angle?

Answer 34

Bent, <109.5

Question 35

How does metallic bonding result?

Answer 35

It is the result of attraction between a lattice of ions and delocalized e-

Question 36

What does the strength of metallic bonding depend on?

Answer 36

Ionic charge

Question 37

Why are metals conductive and shiny?

Answer 37

Delocalized e- carry current and reflect light

Question 38

Why are metals malleable and ductile?

Answer 38

Layers of metal can slide over each other without breaking

Question 39

When are metals most/least conductive?

Answer 39

Most as aqueous or liquids, least as gases

Question 40

What is an alloy?

Answer 40

Mixture of different metals melted and cooled

Question 41

Why do alloys have enhanced properties?

Answer 41

Adding other metals alters the original metals' properties

Question 42

Why is alloy production possible?

Answer 42

Delocalized e- are nondirectional, and the lattice can accommodate different sized ions

Question 43

Why are alloys stronger than pure metals?

Answer 43

Different ions disturb regular network of cations, so it is harder for the layers to slide

Question 44

What is the difference between intermolecular and intramolecular forces?

Answer 44

Intermolecular=between molecules. Intra=between atoms

Question 45

What are the three types of intermolecular forces in order of weakest to strongest?

Answer 45

London dispersion/van der waal, Dipole-diploe, hydrogen bonds

Question 46

What are London dispersion forces?

Answer 46

Temporary attractions created by random clusters of e- that induce temporary dipoles. Causes nonpolar substances to condense in low temperatures

Question 47

What are dipole dipole forces?

Answer 47

When a + end of a polar molecule attracts the - end of another polar molecule. Molecules must be close together, like in a liquid

Question 48

What are hydrogen bonds?

Answer 48

attraction between a slightly positive H on one molecule and a slightly negative atom on another molecule. When the atom is F, O, or N, it is particularly strong since their electronegativity is high