It's time for another Periodic Table of Videos top five.
This selection comes from Professor Luis Brudna, in Brazil.
Luis is a great friend of our project because he has translated more than 100 of our videos in Portuguese.
Here are the five films he likes best, with short comments on each.
1. CESIUM (or CAESIUM)
Luis says: "In Brazil, Cesium has a bad reputation in order of a terrible radiological accident involving Cesium-137, this video is a chance to remember that Cesium can be ‘just’ an alkaline metal, still dangerous, but appreciable."
Luis says: "Aluminum - I dedicated a lot of time working with aluminum and it is still in my memory as a lovely metal."
Luis says: "Because I love the internet, laser, trips and safety glasses!"
4 . HYDROGEN
Luis says: "Hydrogen - a classic of the periodic table."
5. CANDLES AT HALLOWEEN
Luis says: "It is impressive the amount of chemistry and history that may be told from a simple candle. And we still have the chance to remember Michael Faraday."
Many thanks to Luis for his top five!