Don't quote me on this but, im not even sure sodium carbonate can produce such a ph.
Carbonates are weak bases, hydroxides are medium or strong bases.
Try sodium hydroxide, calcium hydroxide or even potassium hydroxide.
“Right here and now, one quanta away, there is raging a universe of active intelligence that is transhuman, hyperdimensional, and extremely alien... What is driving religious feeling today is a wish for contact with this other universe.”
― Terence McKenna