Calcium carbide (cac2) is an unusual substance that contains a carbon anion (c2 2- ). the reaction with water involves several steps that occur in rapid succession. cac2 is a salt (notice that its name is similar to sodium chloride). when a salt dissolves in water, ions leave the crystal lattice and enter the aqueous (aq) solution.

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Calcium Carbide (CaC₂) is an unusual substance that contains a carbon anion (C₂²⁻). The reaction with water involves several steps that occur in rapid succession. CaC2 is a salt (notice that its name is similar to sodium chloride). When a salt dissolves in water, ions leave the crystal lattice and enter the aqueous (aq) solution. Write the relevant balanced chemical equation for the dissolution of CaC₂, in water.

CaC₂(s) + 2H₂O(l) → Ca(OH)₂(aq) + C₂H₂(aq)

Explanation:

When a salt dissolves in water, it dissociates in its ions. In the Calcium Carbide, the cation is Ca⁺² and the anion is C₂²⁻, so the reaction is:

CaC₂(s) + 2H₂O(l) → Ca(OH)₂(aq) + C₂H₂(aq)

The base Ca(OH)₂ is soluble, so it will dissociate at Ca⁺ and OH⁻, but the C₂H₂ is stable and doesn't dissociate in the solution.

4d^55s^1 ( third choice)