Gallium (beating heart) - Periodic Table of Videos

Summary

In this intriguing video, the presenter demonstrates the 'gallium beating heart' experiment, where molten gallium reacts with dilute sulfuric acid, forming gallium sulfate and causing oscillating surface tension changes. The gallium appears to 'beat' like a heart. The video also discusses gallium's melting point, its applications in the electronics industry and medical thermometers, and the recent discovery of a gallium-uranium bond, highlighting the excitement of pioneering new chemical compounds.

Takeaways

• 🔬 The 'gallium beating heart' experiment involves reacting molten gallium with sulfuric acid to demonstrate changes in surface tension.
• 🏵️ Gallium has important applications, contrary to an earlier statement in a video, including in semiconductors and medical thermometers.
• 🤲 The presenter attempts to melt gallium in their hand, highlighting its low melting point compared to other metals.
• 💡 Mendeleev predicted the properties of gallium, which was later discovered and named for its discovery in France.
• 🧪 The experiment shows gallium's surface tension changing from flat to a rounded ball due to the formation of gallium sulfate.
• 🌡️ Gallium forms amalgams with other metals like indium and tin, which are used in medical thermometers as a safer alternative to mercury.
• 🧴 Diluting concentrated sulfuric acid with water is a crucial step in the experiment, done carefully to avoid a violent exothermic reaction.
• 🔄 The 'beating heart' effect is achieved by alternating the surface tension of gallium with the use of dichromate to remove the sulfate.
• 📚 The script mentions a recent scientific breakthrough at Nottingham involving a new compound with a uranium-gallium bond.
• 🎢 The excitement of being the first to create a new compound is likened to a rollercoaster of emotions in the scientific community.
• 🌐 The new uranium-gallium bond represents a significant addition to the periodic table, marking a first-time discovery.

Q & A

What is the 'gallium beating heart' experiment?

The 'gallium beating heart' experiment involves taking molten gallium and submerging it under a layer of dilute sulfuric acid. The acid reacts with the gallium to form gallium sulfate, which changes the surface tension and causes the gallium to form a ball that oscillates, resembling a beating heart.

Why was the narrator attempting to melt gallium in their hand?

The narrator was attempting to demonstrate the low melting point of gallium, which can be melted by the heat from a human hand, showcasing its unique physical properties.

What is the significance of the bet the narrator mentioned about gallium and caesium?

The bet highlighted a misunderstanding about the melting points of gallium and caesium. The narrator believed gallium had a higher melting point than caesium, which was incorrect. This anecdote emphasizes the importance of accurate scientific knowledge.

What are some applications of gallium mentioned in the script?

Gallium is used in the production of gallium salts for various important applications. It is also particularly important in the creation of new-generation semiconductors used in the electronics industry, and as an amalgam in medical thermometers due to its lower toxicity compared to mercury.

Why is the narrator careful to add acid to water and not the other way around when diluting sulfuric acid?

When diluting concentrated sulfuric acid, it is important to add the acid to water to prevent an exothermic reaction that could cause the mixture to splash or spray, potentially causing injury.

What is the role of dichromate in the 'gallium beating heart' experiment?

Dichromate acts as an oxidant in the experiment. It is used to remove the gallium sulfate from the surface of the gallium, allowing the gallium to flatten. When the right amount of dichromate is added, it can induce the oscillating 'beating heart' effect.

Why was Mendeleev able to predict the properties of gallium before it was discovered?

Mendeleev was able to predict the properties of gallium based on his understanding of the periodic table and the trends among elements. He named the predicted element eka-aluminium, and it was discovered shortly after, confirming his predictions.

What is the significance of the new compound formed by Steve Liddle involving uranium and gallium?

The new compound is significant because it represents the first time a bond between uranium and gallium atoms has been observed. This discovery expands our understanding of chemical bonding and the potential for new materials.

What does the narrator mean by 'being a chemist is like being on a rollercoaster'?

The narrator is expressing the highs and lows of scientific research. There are challenging days when progress is slow, but also exhilarating moments of discovery and innovation, such as being the first to create a new compound.

What is the significance of the 'new union' mentioned at the end of the script?

The 'new union' refers to the formation of a new chemical bond between uranium and gallium atoms. This discovery is a significant contribution to the field of chemistry and represents a unique achievement for the researchers at Nottingham.