Why is beryllium different from other alkaline earth metals?

Beryllium is different due to its small size, high ionization energy, and tendency to form covalent compounds.

Group 2: Alkaline Earth Metals

Q: Why are Group 2 elements called alkaline earth metals?

They are called alkaline earth metals because their oxides and hydroxides are alkaline in nature and occur in the earth’s crust.

Q: Which is the most abundant alkaline earth metal in the human body?

Calcium (Ca) is the most abundant alkaline earth metal in the human body, essential for bones and teeth.

Group 2 elements of the periodic table are known as the Alkaline Earth Metals. This group includes Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra). These metals are shiny, silvery-white, and moderately reactive — less than Group 1 alkali metals.

Group - Alkaline Earth Metals — Group – Alkaline Earth Metals

Electronic Configuration & General Features

All alkaline earth metals have two electrons in their outermost shell, with general configuration ns^2. Key features:

Readily lose two valence electrons to form M²⁺ ions.
Exhibit a stable oxidation state of +2.
Higher ionization energy and smaller radii than Group 1 Alkali Metals.

Physical Properties

Harder with higher melting points than alkali metals.
Show metallic luster; moderately reactive.
Density increases down the group (Be is an exception).
Good conductors of heat and electricity.

Chemical Properties

With Water: React to form hydroxides and H₂ gas (Be does not react easily).
With Oxygen: Form basic oxides (MO).
With Halogens: Form ionic halides (MX₂), except Be halides (covalent).
Thermal Stability: Carbonates & nitrates become more stable down the group.

Important Compounds & Uses

CaCO₃: In limestone, cement, chalk, dietary supplement.
MgSO₄ (Epsom salt): Medicine & agriculture.
BaSO₄: Radiocontrast agent in imaging.
Be alloys: For springs, tools, electrical contacts.
Ra: Historically used in luminous paints (now discontinued).

Trends in Group 2

– Atomic/ionic radii ↑ down the group
– Ionization energy ↓ → Reactivity ↑
– Metallic character ↑
– Carbonates & nitrates become more thermally stable
– Hydroxide solubility ↑ down the group

MCQ Quiz: Test Your Knowledge

General electronic configuration of Group 2 elements is:
a) ns¹ b) ns² c) np² d) (n-1)d¹⁰ns²
Answer: b) ns²
Which alkaline earth metal does not react with water easily?
Answer: Beryllium (Be)
Formula of calcium oxide is:
Answer: CaO
Which property increases down Group 2?
Answer: Reactivity with water

FAQs on Alkaline Earth Metals

Q1: Why are Group 2 elements called alkaline earth metals?
Ans: Because their oxides and hydroxides are alkaline in nature and occur in earth’s crust.

Q2: Which is the most abundant alkaline earth metal in the human body?
Ans: Calcium (Ca), vital for bones and teeth.

Q3: Why is beryllium different from other group members?
Ans: Due to small size, high ionization energy, and covalent bonding tendency.