explaining matter: chemical change - part 6 of 18. illustrates that a chemical change takes place when atoms from the molecules of two or more materials join to form molecules of entirely different materials. examples of changes include burning, digestion - potassium 個影片檔及 b 捲影像00:29
cutting potassium metal with a scalpel. the shiny exposed metal surface reacts rapidly with oxygen and water in the air, forming a duller layer of potassium oxide and hydroxide - potassium 個影片檔及 b 捲影像00:25
cutting potassium metal with a scalpel. the shiny exposed metal surface reacts rapidly with oxygen and water in the air, forming a duller layer of potassium oxide and hydroxide - potassium 個影片檔及 b 捲影像00:34
cutting potassium metal with a scalpel. the shiny exposed metal surface reacts rapidly with oxygen and water in the air, forming a duller layer of potassium oxide and hydroxide - potassium 個影片檔及 b 捲影像00:55
1983 montage volcanoes erupting and clouds moving while discussing radiation / iceland - potassium 個影片檔及 b 捲影像00:19
healthy eating: small pieces of strawberry falling in yogurt of the same flavour, slow motion - potassium 個影片檔及 b 捲影像00:05
in a clandestine outpost in nicaragua a man sporting sunglasses and a blue face protector hand mixes mortar bombs: a concoction of potassium chlorate... - potassium 個影片檔及 b 捲 影像02:55