What is the Difference Between Barium and Strontium

The key difference between barium and strontium is that barium metal is more chemically reactive than strontium metal.

Barium and strontium are two members of the alkaline earth metals group (group 2) of the periodic table. This is because these metal atoms have an ns² electron configuration. Although they are in the same group, they belong to different periods, which makes them slightly different from each other in their properties.

1. Overview and Key Difference
2. What is Barium
3. What is Strontium
4. Barium vs Strontium in Tabular Form
5. Summary – Barium vs Strontium

What is Barium?

Barium is a chemical element having the symbol Ba and atomic number 56. It appears as a silvery-gray metal with a pale yellow tint. Upon oxidation in air, the silvery-white appearance suddenly fades to give a dark grey layer consisting of the oxide. This chemical element is found in the periodic table in group 2 and period 6 under alkaline earth metals. It is an s-block element with the electron configuration [Xe]6s2. It is a solid at standard temperature and pressure. It has a high melting point (1000 K) and a high boiling point (2118 K). The density is very high as well (about 3.5 g/cm³).

Barium and Strontium - Side by Side Comparison

Figure 01: Silvery White Barium

The natural occurrence of barium can be described as primordial, and it has a body-centered cubic crystal structure. Moreover, barium is a paramagnetic substance. More importantly, barium has a moderate specific weight and a high electrical conductivity. This is because this metal is difficult to purify, which makes it difficult to figure out most of its properties. When considering its chemical reactivity, barium has a reactivity similar to magnesium, calcium, and strontium. However, barium is more reactive than these metals. The normal oxidation state of barium is +2. Recently, research studies have found a +1 barium form as well. Barium can react with chalcogens in the form of exothermic reactions, releasing energy. Therefore, metallic barium is stored under oil or in an inert atmosphere.

What is Strontium?

Strontium is a chemical element having the symbol Sr and atomic number 38. It is an alkaline earth metal in group 2 and period 5 of the periodic table. It is a solid at standard temperature and pressure. The melting point of strontium is high (1050 K), and the boiling point is also high (1650 K). Its density is high as well. It is an s block element with the electron configuration [Kr]5s2.

Figure 02: Strontium Crystal

Strontium can be described as a divalent silvery metal having a pale yellow tint. The properties of this metal are intermediate between the neighboring chemical elements calcium and barium. This metal is softer than calcium and harder than barium. Similarly, the density of strontium is in between calcium and barium. There are three allotropes of strontium as well.

Figure 03: The Oxidized Form of Strontium

Strontium shows high reactivity with water and oxygen. Therefore, it naturally occurs only in compounds alongside other elements like strontianite and celestine. Moreover, we need to keep it under liquid hydrocarbons such as mineral oil or kerosene to avoid oxidation. However, fresh strontium metal rapidly turns into a yellow color when exposed to air because of the formation of the oxide.

What is the Difference Between Barium and Strontium?

Barium and strontium are important alkaline earth metals in group 2 of the periodic table. The key difference between barium and strontium is that barium metal is more chemically reactive than strontium metal. Moreover, barium is comparatively softer than strontium.

The below infographic presents the differences between barium and strontium in tabular form for side-by-side comparison.

Summary – Barium vs Strontium

Barium is a chemical element having the symbol Ba and atomic number 56, while Strontium is a chemical element having the symbol Sr and atomic number 38. The key difference between barium and strontium is that barium metal is more chemically reactive than strontium metal.

Reference:

1. “Barium – Element Information, Properties and Uses: Periodic Table.” The Royalty Society of Chemistry.

Image Courtesy:

1. “Barium unter Argon Schutzgas Atmosphäre” By Matthias Zepper – (Public Domain) via Commons Wikimedia
2. “Strontium destilled crystals” By Alchemist-hp (talk) – Own work (FAL) via Commons Wikimedia
3. “Strontium 1” By The original uploader was Tomihahndorf at German Wikipedia. – Transferred from de.wikipedia to Commons. (CC BY-SA 3.0) via Commons Wikimedia