The coefficient is needed in front of NaNO3 to balance the equation is 2.
When in a chemical reaction, both the product elements or compounds should have number of moles equal to that of the elements or compounds of reactants.
In the given chemical reaction equation,
Na2S + Zn(NO3)2 → ZnS + _NaNO3
Number of moles of S is 1 on both the product and reactant side. Zn has 1 mole on both side. NO3 has 2 mole and Na has 2 mole on reactant side. So to balance the equation, Na and NO3 both must have 2 moles on product side.
Thus, the coefficient is needed in front of NaNO3 to balance the equation is 2.
Learn more about balanced equation.
https://brainly.com/question/11322377
#SPJ1