MODULE 2.1

Question 1

Chemical Bonds

Answer 1

Formation of different types of compounds (polar covalent non-polar covalent and ionic compounds, including coordinate covalent compounds)

Question 2

We encounter these types of compounds as ________________.

Answer 2

pollutant substances

Question 3

Stability of Noble Gases (Fact, Theory, Deduction)

Answer 3

1. Fact - Noble gases are inert. They undergo few chemical reactions; follow Octet rule.
2. Theory - This inertness is due to their electronic structure; filled outermost energy levels.
3. Deduction - If other elements could alter their structures to be like noble gases, they would also become less reactive.

Question 4

[EXAMPLE] Sodium ion (Na+) is ISOELECTRONIC with Ne. Does that mean they are identical?

Answer 4

Since the identity of the element is equivalent to the number of protons, sodium ion is NOT IDENTICAL to neon; it only BEHAVES like one as it will have the same electronic configuration.

Question 5

[EXAMPLE] Sodium ion (Na+) is ISOELECTRONIC with Ne. Does that mean they are identical?

Answer 5

Since the identity of the element is equivalent to the number of protons, sodium ion is NOT IDENTICAL to neon; it only BEHAVES like one as it will have the same electronic configuration.

Question 6

Explain the process of METALS and NONMETALS.

Answer 6

Metals lose electrons; main group metals lose electrons equivalent to their family number —-> Non-metals gain electrons; main group non-metals gain (8-family number) amount of electrons.

*Transition Metals lose varying amounts of electrons.

Question 7

The Chemical Bond is a force that holds atoms together. What is its principle in terms of stability?

Answer 7

• Atoms interact in order to achieve stability.
• Any atom can be stable by giving off or receiving electrons/sharing electrons

Question 8

What are the types of chemical bonds?

Answer 8

• Ionic
• Covalent (Polar - sharing electrons inequally, Non-polar - sharing electrons equally)

Question 9

Rule for naming CATIONS

Answer 9

Retain original name

Question 10

Rule for naming CATIONS

Answer 10

Retain original name

Question 11

Rule for naming ANIONS

Answer 11

Base element + ide

Question 12

Rule for naming ionic compounds

Answer 12

Cation + Anion

Question 13

Ionic Bonding (4 principles)

Answer 13

• Formed due to a transfer of electron/s.
• Formed between a metal and a non-metal.
• Formed due to a large difference in electronegativity.
• In the process, cations (+) and anions (+) are formed.

Question 14

What are ions held together by?

Answer 14

Electrostatic Interaction; held together by interparticle forces (IPFs) as opposed to IMFs

Question 15

Lewis Symbol

Answer 15

Gives the symbol of the element and its valence electrons; the family represents the no. of valence electrons.

Question 16

Positive and negative ions attract each othet to form a 3d lattice

Answer 16

Ionic Lattice

Question 17

The melting and boiling points of ionic solids

Answer 17

high; large amount of thermal energy is required to separate the ions which are bound by strong electrostatic forces.

Question 18

Electrical conductivity

Answer 18

solid ionic compouds do not conduct electricity when potential is applied because there are no mobile charged particles.

Question 19

Hardness of ionic solids

Answer 19

most ionic compounds are hard; their surfaces of their crystals are not easily scratched. ions are bound strongly to the lattice and aren’t easily displaced.

Question 20

Brittleness of ionic solids

Answer 20

brittle; crystal will shatter when distorted. distortion cause ions of like charges to come close together then sharply repel.

Question 21

rule for pair of non-metals forming more than 1 compound (N, O, P, Cl, S, C, F)

Answer 21

Use Greek prefixes: mono, di, tri, tetra, penta, hexa, hepta, octa, nona, deca

Question 22

equal sharing of electrons; no difference or very small difference in electronegativity; no net dipole moment

Answer 22

Non-polar covalent bond

Question 23

unequal sharing of electrons; electronegativity difference not equal to zero; net dipole moment

Answer 23

Polar covalent bond

Question 24

combination of lewis symbols; atoms form stable compounds to achieve noble gas electronic configurations; elements tend to be surrounded by eight electrons (octet) except for H and He where a duet applies.

Answer 24

Lewis Structures

Question 25

Components of the earth’s atmosphere

Answer 25

Nitrogen - 78 percent
Oxygen - 21 percent
Argon - 0.93 percent
Carbon dioxide - 0.04 percent

Question 26

Why does Nitrogen and Oxygen make up most of the atmosphere?

Answer 26

THey’re plentiful because they’re the most stable (N - triple bond; O - double bond)