posted by Fiona .
I have an assigment question that I need help with.
The Q states that sodium hydroxide absorbs water from the atmosphere. Then the saturated NaOH absorbs carbon dioxide from the air to form a thin coating of sodium carbonate.
A piece of sodium hydroxide has been left on a watch glass. It is then dried, dissolved in water and excess barium nitrate solution is added. Is the precipitate that forms barium carbonate?
yes, barium carbonate is insoluble.
Yes I know that barium carbonate is soluble. What I wanted to know is: is barium carbonate the likely precipitate in this equation.
The solubilities are quite different.
BaCO3 0.002 g per 100 ml
Ba(OH)2 5.6 g per 100 ml
(both in cold water)
so yes, barium carbonate is the most likely ppt.