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 - 鉀 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 - 鉀 個影片檔及 b 捲影像00:34
view factory with smoke stacks / men riding atv underground / huge mining machine cuts into the bed rock / collected rock on back of truck / rock... - 鉀 個影片檔及 b 捲影像01:14
explaining matter: chemical change - part 9 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 - 鉀 個影片檔及 b 捲影像00:30
explaining matter: chemical change - part 7 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 - 鉀 個影片檔及 b 捲影像00:32
explaining matter: chemical change - part 5 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 - 鉀 個影片檔及 b 捲影像00:34
an aerial footage from jordan’s western dead sea region shows the natural beauties surrounding the lake also known as the salt sea.the lake, a... - 鉀 個影片檔及 b 捲影像01:57無人機角度
in a clandestine outpost in nicaragua a man sporting sunglasses and a blue face protector hand mixes mortar bombs: a concoction of potassium chlorate... - 鉀 個影片檔及 b 捲影像02:55
