Jawapan Paling Bijak!
For preparation of insoluble salt ,
you just need to choose two soluble salts that have the cation and anion of the salt
: Barium Nitrate and Sodium sulphate
2) if zinc nitrate is being heated .. it will decomposr into zinc oxide and release nitrogen dioxide and oxygen ..the zinc oxide is yellow when hot white when cold ( you can remember it like summer( yellow ) and winter(white) )
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