Please help this affects my grade a lot and im confused Double Replacement/Combustion I need to find the product of each one
zinc oxide + Cobalt(III) nitrite
Calcium hydroxide + phosphoric acid
Copper(I) dichromate + Iron(III) arsenate
Hydrochloric acid + aluminum hydroxide

1 ) Cobalt(II) nitrate react with nitrate zinc(II) to produce cobalt(III)-zinc oxide, nitrogen dioxide and oxygen  

2Co(NO3)2 + Zn(NO3)2 → Co2ZnO4 + 6NO2 + O2

2) Calcium hydroxide react with phosphoric acid to produce calcium, hydrogen phosphate and water

Ca(OH)2 + H3PO4 → CaHPO4 + 2H2O

3) Copper(II) dichromate will react with Iron(III) arsenate to form Copper(II) Arsenate and Iron(III) dichromate

3Cr2CuO7 + 2AsFeO4 → Cu3(AsO4)2 + Fe2(Cr2O7)3

Reaction Type : Double Displacement

4) aluminium hydroxide and hydrochloric acid react to form aluminium chloride and water

Al(OH)3 + 3HCl → AlCl3 + 3H2O

answer: mercury

explanation:

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