Question

example of a double displacement reaction will be
1.metal with salt
2.metal with an acid
3.metal with metal
4.salt with a salt ​

Answer 1

It's 4. salt with a salt

for example: CuSo4 + Nacl -> Na2So4 + CuCl2

Na2So4 + BaCl2 -> BaSo4 + Nacl

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