2007-12-17 08:18:51 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
What has been standing for awhile? NaOH solution or precipitate? In air or in closed container.
As Paul B pointed out, if Mn(OH)2 is exposed to air, it will turn into brown MnO2. If it is standing in a closed flask, than nothing will happen.
If NaOH was standing for awhile, it would have some Na2CO3 formed in it (due to CO2 absorption from air). Then, reaction with Mn(II) will yield MnCO3 instead of Mn(OH)2. MnCO3 is more stable in O2 and nothing will happen even if this precipitate will be kept in air.
2007-12-17 09:29:30 · answer #1 · answered by Anonymous · 0⤊ 0⤋
Did you do this experiment? If so, what did you see?
Under basic conditions, pale pink Mn(OH)2 gets oxidised by air to very dark brown MnO2, but unless you saw this or were told it, I don't see how you're expected to know that.
2007-12-17 08:28:45 · answer #2 · answered by Facts Matter 7 · 0⤊ 0⤋