Periodic Trends Project - Period 2

Period 2 Trend: Electronegativity

As you move to the right across a period of elements, electronegativity increases. As for transition metals, while they have values, there is little variance among them as you move across the period.

Period 2 Trend: Reactivity

Boiling Point &Melting Point:

Metallic Character for Each Element:

In metals, reactivity decreases as you go across a period left to right. In non-metals, reactivity increases as you go across a period left to right.

Lithium (Li)

Boiling Point: 1347.0° C

Melting Point: 180.54° C

Beryllium (Be)

Boiling Point: 2970.0° C

Melting Point: 1278.0° C

Boron (B)

Boiling Point: 2550.0° C

Melting Point: 2300.0° C

Carbon (C)

Boiling Point: 4827.0° C

Melting Point: 3500.0° C

More Boiling & Melting Points

Lithium is an alkali metal and has one electron in its outer shell, which is loosely bound. It is the least dense of all alkali metals and highly reactive. Lithium is also a soft metal and has a low ionization energy.

Beryllium is a steel-gray metal that tarnishes slowly in the air due to oxide forming around it. With a small atomic radius, Be2+ has high polarization characteristics allowing it to form many covalent bonds. Beryllium forms an oxide layer making it not react with air or water even in extreme heat. Beryllium dissolves easily in non-oxidizing acid.

Nitrogen (N)

Boiling Point: -195.8° C

Melting Point: -209.9° C

Oxygen (O)

Boiling Point: -183.0° C

Melting Point: -218.4° C

Fluorine (F)

Boiling Point: -188.14° C

Melting Point: -219.62° C

Neon (Ne)

Boiling Point: -246.1° C

Melting Point: -248.6° C

Noble Gas Configurations:

More Noble Gas Configurations:

Lithium Li = [He] 2s1

Beryllium Be = [He] 2s2

Boron B = [He] 2s22p1

Carbon C = [He] 2s22p2

Metallic Character for Each Element:

Nitrogen N = [He] 2s22p3

Oxygen O = [He] 2s22p4

Fluorine F = [He] 2s22p5

Neon Ne = [He] 2s22p6

Fluorine exists as a diatomic molecule in its free state (F2) and is the most abundant halogen found in the Earth’s crust. Fluorine is the most electronegative element out of all of the elements in the Periodic Table. It appears as a pale yellow gas at room temperature. Fluorine is extremely reactive and reacts directly with all elements except helium (He), neon (Ne), and argon (Ar).

Neon is the fourth most abundant element in the entire universe, behind hydrogen, helium, and oxygen. However, it is considered very rare on Earth as it can mainly be found in the atmosphere. This is because it is highly inert, very light, and has high vapor pressure at low temperatures. Neon is the second lightest noble gas and is a monatomic gas.

Elements & Symbols in Period 2

Period 2 Trend: Ionic Radii

Periodic Trends Project - Period 2

As you move to the right across a period in the Periodic Table, the ionic radius decreases for metals forming cations, while the ionic radius increases for non-metals.

Li (Lithium)

Be (Beryllium)

B (Boron)

C (Carbon)

N (Nitrogen)

O (Oxygen)

F (Fluorine)

Ne (Neon)

State of Matter:

Metallic Character for Each Element:

Nitrogen has the highest electronegativity, which illustrates it is the most nonmetallic of the group. The common oxidation states of nitrogen are +5, +3, and -3. Nitrogen makes up 78% of the volume in the Earth’s atmosphere. Natural sources of nitrogen can be found in animal/plant proteins and in fossilized remains of ancient plant life.

Oxygen is a gas at room temperature and 1 atm. It is colorless, odorless, and tasteless. Oxygen is the most abundant element by mass in both the Earth’s crust and the human body. It is second to nitrogen as the most abundant element in the atmosphere.

Lithium - Solid (Nonmagnetic)

Beryllium - Solid (Nonmagnetic)

Boron - Solid (Nonmagnetic)

Carbon - Solid (Nonmagnetic)

Period 2 Trend: Valence Electrons

More States of Matter:

The number of valence electrons increases by one valence electron going left to right across the period. For Period 2, all elements have valence electrons in the second energy level.

Nitrogen - Gas

Oxygen - Gas (Paramagnetic)

Fluorine - Gas (Nonmagnetic)

Neon - Gas (Nonmagnetic)

Period 2 Trend: Atomic Radii

The trend is as you move left to right across a period, the atomic radius decreases.

Trent Allen

Period 2 Trend: Ionization Energy

Metallic Character for Each Element:

Generally, elements on the right side of the Periodic Table have higher ionization energy. In other words, going left to right across the period ionization energy increases.

Lewis Dot Structures:

Boron is the top element of group 13 and is the only semi-metal of this group. It has properties of a metal and a non-metal. It has an oxidation state of +3. This element does not exist alone. It forms compounds, which can be widely found in the Earth’s crust.

Carbon is the fourth most abundant element on earth. Carbon is a very special element. It’s what makes organic molecules organic. It has two important qualities: small size and a unique electron configuration. Since it’s small, the p-orbital electrons overlap considerably and enable pi bonds to form.

Li Be B

C N O

F Ne