Why does Turmeric glow under black light?

Summary

In this 'Glow-in-the-Dark Science Experiments' video, the host explores the unexpected fluorescence of turmeric under a black light. Using curcumin, the pigment in turmeric, the video demonstrates how turmeric glows when dissolved in alcohol, contrasting with its lack of fluorescence in water due to curcumin's hydrophobic nature. The experiment also tests other spices in various liquids, revealing that while turmeric stands out, cumin and paprika show potential for fluorescence as well.

Takeaways

• 🔬 The video is part of a 'Glow-in-the-Dark Science Experiments' series, focusing on turmeric's fluorescent properties under UV light.
• 🌟 Turmeric contains a naturally fluorescent chemical called curcumin, which is responsible for its bright yellow color.
• 🧪 To observe turmeric's fluorescence, it's necessary to disperse its particles, which can be achieved by dissolving it in a liquid.
• 💧 Turmeric does not fluoresce in water due to its insolubility, keeping the curcumin particles clumped together.
• 🍾 Turmeric does fluoresce in 70% isopropyl alcohol, allowing the curcumin to spread out and absorb UV light effectively.
• 🎨 The video demonstrates the beautiful glowing effect of turmeric in alcohol under a black light, resembling artwork.
• 🌞 Curcumin is hydrophobic, meaning it repels water, which is why it's often mixed with fats or oils in cooking rather than water.
• 🥃 Experiments with vegetable oil show that turmeric does fluoresce, but the effect is less dramatic due to the oil's own fluorescence.
• 🧂 Other spices tested, such as salt and cinnamon, do not fluoresce, while cumin and paprika show potential but are not as vibrant as turmeric.
• 👀 The video suggests that the viewer's personal experience may vary and encourages trying different substances to see their fluorescent properties.
• 📚 The script ends with an invitation to explore more glow-in-the-dark experiments and to stay curious and keep learning.

Q & A

What is the main topic of the video?

The main topic of the video is about conducting a glow-in-the-dark science experiment using turmeric.

What is the purpose of using a black light in the experiment?

The purpose of using a black light is to provide ultraviolet light, which is absorbed by fluorescent substances and then remitted as visible light, making them glow.

What is fluorescence and how is it related to the experiment?

Fluorescence is the property of a substance to absorb light and re-emit it as visible light. It is related to the experiment because turmeric contains a naturally fluorescent chemical called curcumin.

Why does the turmeric glow under a black light?

The turmeric glows under a black light because it contains curcumin, which is a naturally fluorescent chemical that absorbs ultraviolet light and emits visible light.

What is the chemical in turmeric that makes it glow?

The chemical in turmeric that makes it glow is curcumin, which is responsible for the bright yellow pigment in turmeric.

Why doesn't turmeric fluoresce well in water?

Turmeric doesn't fluoresce well in water because it is not soluble in water, keeping the curcumin particles clumped together and reducing the surface area available to absorb ultraviolet light.

What type of alcohol is used in the experiment and why?

70% isopropyl alcohol is used in the experiment because it dissolves the curcumin in turmeric, providing more surface area for the absorption of ultraviolet light and enhancing fluorescence.

Why is turmeric not soluble in water but soluble in alcohol?

Turmeric is not soluble in water because curcumin is hydrophobic, meaning it repels water. Alcohol, on the other hand, dissolves curcumin, allowing it to spread out and absorb light.

What happens when turmeric is mixed with oil in the experiment?

When turmeric is mixed with oil, it fluoresces, but not as dramatically as in alcohol because the oil itself is also fluorescent and the contrast is less pronounced.

What other household spices were tested for fluorescence in the video?

Other household spices tested for fluorescence in the video include salt, cinnamon, cumin, and paprika.

What was the conclusion about the fluorescence of the other spices tested?

The conclusion was that salt and cinnamon did not fluoresce, while cumin and paprika showed some fluorescence, although not as strong as turmeric.