想知道某幾隻 metal oxide & hydroxide 有邊隻可溶於水 & 顏色

Potassium oxide - yes - white
Sodium oxide - yes - white
Calcium oxide - slightly yes - white
Magnesium oxide - no - white
Aluminium oxide - no - white
Zinc oxide - no - white in cold, yellow in hot
Iron(II) oxide - no - black
Iron(III) oxide - no - reddish (or reddish brown)
Iron(II) iron(III) oxide - no - black
Lead(II) oxide - no - yellow in cold, brown/orange in hot
Copper(I) oxide - no - black
Copper(II) oxide - no -black
Silver oxide - no - dark brown

N.B.
(1) Oxide ions cannot exist in water. “A soluble metal oxide” means that the oxide reacts with water to give a soluble metal hydroxide.
(2) The colours shown above are the colours of the oxides in solid state.

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Potassium hydroxide - yes - white
Sodium hydroxide - yes - white
Calcium hydroxide - slightly yes - white
Magnesium hydroxide - no - white
Aluminium hydroxide - no - white
Zinc hydroxide - no - white
Iron(II) hydroxide - no - dirty green
Iron(III) hydroxide - no - reddish brown
Lead(II) hydroxide - no - white
Copper(II) hydroxide - no -blue
Silver hydroxide - no - white
(Silver hydroxide is unstable which decomposes rapidly to silver oxide at room condition.)

N.B.
(1) All solutions of the above soluble hydroxides are colourless.
(2) The colours shown above are the colours of the hydroxides in solid state.