Boron - Periodic Table of Videos

Summary

The speaker expresses a deep fascination with boron, an element they have synthesized during their school years. Boron, a metalloid with atomic number 5, is highlighted for its varied allotropes, including a very hard black crystalline form second only to diamond in hardness. The town of Boron in California, established around the world's largest borax mine, is mentioned. Boron hydrides, particularly pentaborane, are discussed for their historical interest as a rocket fuel with a toxic, green flame. Boron compounds, notably perborate, are also mentioned for their use in laundry detergents like Persil, which contains a mixture of perborate and silicate. The demonstration of benzene boronic acid burning with a green flame concludes the talk, emphasizing the element's unique properties.

Takeaways

• 🔬 The speaker has a strong affinity for boron, an element they have worked with extensively in chemistry.
• 📚 Boron is a metalloid with atomic number 5, possessing properties of both metals and non-metals.
• 💥 The speaker describes a dramatic chemical reaction involving boron oxide and magnesium, resulting in bursts of gas that ignite like anti-aircraft guns.
• 🏜 Elemental boron is a brown powder with several crystalline forms, one of which is extremely hard and just below diamond on the Mohs scale.
• 📍 There's a town named Boron in California, established around the world's largest borax mine.
• 🚂 Borax was historically transported by mules, and the company's trademark featured a train of 20 mules.
• 🔍 Boron hydrides, or borides, are clusters of boron atoms surrounded by hydrogen, which have been of significant interest to chemists for decades.
• 🔥 Pentaborane, a boron hydride with five boron atoms, was studied as a rocket fuel during the Cold War due to its intense green flame and high toxicity.
• 🧼 Boron compounds, such as perborate, are used in cleaning products like washing powders, where they release hydrogen peroxide to bleach clothes.
• 👕 The brand Persil derives its name from the combination of 'perborate' and 'silicate', indicating its key ingredients.
• 🔥 Benzene boronic acid, an organic compound containing boron, can burn with a green flame, as demonstrated by the speaker.

Q & A

Why does the speaker have a fondness for boron?

The speaker has a fondness for boron because they used to do a lot of chemistry with it and find it interesting. They also made elemental boron themselves when they were at school.

What is boron's position in the periodic table and what does that signify?

Boron sits on top of group 13 with an atomic number of 5, signifying that it is a metalloid, having properties of both metals and non-metals.

Can you describe the reaction the speaker had with boron oxide and magnesium?

The speaker mixed an oxide of boron with magnesium, heated it, and then added water at the end to destroy the magnesium boride formed. This resulted in a dramatic reaction with puffs of gas that burst into flames, resembling little anti-aircraft guns.

What is the appearance of elemental boron?

Elemental boron is a brown powder, with several crystalline types of allotropes, one of which is very hard and just below diamond on the Mohs scale of hardness.

What is the significance of the town of Boron in California?

The town of Boron in California was set up around the world's biggest borax mine and has a population of around 2000. It was named after the element boron.

What was the historical transportation method for borax from the mine in California?

Historically, borax was transported on trains of mules, and the company that produced it had a trademark featuring a train of 20 mules.

What are boron hydrides and why are they of interest to chemists?

Boron hydrides are clusters of borons with hydrogens around them. They have been of great interest to chemists for over 50 to 70 years due to their unique properties and potential applications.

What was pentaborane, and why was it significant during the Cold War?

Pentaborane is a boron hydride with five borons in it. It was investigated during the early part of the Cold War as a potential rocket fuel because it burns with a very hot green flame.

Why was pentaborane referred to as the 'green dragon'?

Pentaborane was referred to as the 'green dragon' because it burns with a very hot green flame and is also highly toxic.

What is the role of perborate in washing powders and why is it significant?

Perborate is used in washing powders, particularly when heated in a washing machine at 60 degrees centigrade, it turns into hydrogen peroxide which can bleach clothes. This is why the famous washing powder is called Persil, as 'per' stands for perborate and 'sil' stands for silicate.

What is benzene boronic acid and how does it relate to the experiment described in the script?

Benzene boronic acid is an organic compound containing boron. In the script, it is mentioned as a compound that can burn with a green flame, similar to pentaborane, but without the risk of spontaneous combustion in air.