[geubrina]

I want to buy some Zinc Powder or Zinc metal, but in my town, the zinc powder's price is more than USD 100 per kg. However, I found ZnSO4 at USD 1.2/kg.

Can I make the zinc powder by adding the ZnSO4 to NaOH?

ZnSO4 + 2NaOH ---> Zn(s) + Na2SO4 + H2O

Please guide me....

[Arkcon]

I don't believe NaOH has the reducing power to form free Zn.  Sodium is more electropositive than zinc, and will not exchange easily.  Certainly, nothing useful will happen in aqueous solution.  If you really want to make your own zinc, you might try roasting it to the oxide, and maybe reducing it to Zn with carbon, under say, borate salts as a flux.  I used to play with US pennies in that fashion, they are simply a thin plating of copper over zinc.  But you're not likely to save money with these machinations.  Zinc and other such reactive metals are usually produced electrolytically, from the melt, hence the price.

[geubrina]

I think I must correct it:

2NaOH + ZnSO4 --> Na2SO4 +ZnO + H2O.

Is this reaction possible?

[AWK]

Not exactly

ZnSO4 + 2 NaOH = Na2SO4 + Zn(OH)2

Zn(OH)2 when heated can form ZnO

[netthubuon]

geubrina said to obtain Zn metal. You say when heated Zn(OH)2 is obtained ZnO. How is not obtained Zn?

[BluRay]

geubrina said to obtain Zn metal. You say when heated Zn(OH)2 is obtained ZnO. How is not obtained Zn?

You have to reduce the oxide to get the metal. You can do it even with coal, probably  at a reasonable temperature (that is, not extremely high).

About the reaction between zinc sulfate and sodium hydroxide, it should not be used an excess of sodium hydroxide, or the zinc hydroxide will dissolve again after precipitation, forming hydroxy zincate ion Zn(OH)₄^-.

[aieeee]

i agree with blueray. the reaction is :
ZnSO4 + 2 NaOH = Na2SO4 + Zn(OH)2 (white ppt.) + H2

and when NaOH is in excess then soluble complex Zn(OH)₄^-( can also be written as ZnO₂^2-+H₂O) is obtained.

this is a misconception that anything like Zn or ZnO is obtainewd by heating Zn(OH)2 , as its a precipitate.

[Borek]

ZnSO4 + 2 NaOH = Na2SO4 + Zn(OH)2 (white ppt.) + H2

Have you tried to balance this reaction?