Question

___co+__ Na2s--> ___ Na+ ___ cos2

Answer 1

Answer: $Co+2Na_2S\rightarrow 4Na+CoS_2$

Explanation:

According to law of conservation of mass, mass can neither be created nor be destroyed. The atoms on the reactant side must be equal to the number of atoms on the product side so that the mass remains the same on reactant and product side. Thus the reactions are balanced.

Single displacement reaction is one where a more reactive element replaces the lesser reactive one.

The balanced chemical reaction will be:

$Co+2Na_2S\rightarrow 4Na+CoS_2$