Aqua Regia
Here are three samples of gold. We add concentrated hydrochloric acid on the left, concentrated nitric acid on the right, and a mixture of the two in the middle. The gold reacts with the concentrated acid mixture which is referred to as aqua regia, meaning "royal water".
The size of the movie file is 5.1 MB and its duration is 78 seconds. The name of the movie file is "AQREGIA.MOV" and it is located in the folder "MOVIES/AQREGIA".
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