Wow! I never thought some metals would dramatically react on water... pretty impressed!
I'm a chemistry teacher and have to say that they took away the excitement that should be in any video of the alkali metals. The video's showing of Sodium in water was a let down. I've taught this with an approx. 1 cm cubed piece of sodium that I've made cuts into all sides of to expose more surface area and upon dropping it into a bucket of water made such an explosion that it frightened nearby classrooms and busted the bucket. Another teacher did a similar demo with a smaller piece of sodium and without exposing more surface and caught the grass on fire.
This my friends, is why Chemistry is the bomb-digity.
I love science
Let's try cesium, he said.
cesium is made of awesome!
"You can see that things gradually become more terrifying as we move down the group" Indeed.