What exactly is "sodium carbonate"? How do I get it?

[behindthelight]

I know it's like baking soda or baking powder right? I am trying to do the Tao of Rue extraction and at the end he says to use sodium carbonate. I just need to find out what exactly it is.

Thanks.

 

[DeMenTed]

Bake bi-carbonate of soda in the oven at a high heat for an hour and it will magically turn into sodium carbonate

 

[Leon Trout]

or just pick up a box of Arm & Hammer Super Washing Soda... 100% Sodium Carbonate... pretty useful stuff, all around...

 

[behindthelight]

Thanks guys. That is what I needed.