Buttons in mixture machine!!!!

[toretorden]

I'm lost on this. I tried hitting 216453 and nothing.

It's like this :

Spoiler below!

The buttons relate to the chemicals like this :

A C S
B N I

Where S is sulphur, N is nitrogen etc. The right combination then is :

2 1 6
4 5 3

This means you hit the button in the top middle first, then top left, bottom right, bottom left, bottom middle and top right.