Net ionic equation
Cu²⁺(aq)+S²⁻(aq)⇒CuS(s)
<h3>Further explanation</h3>
Double-Replacement reactions. Happens if there is an ion exchange between two ion compounds in the reactant to form two new ion compounds in the product
In the ion equation, there is a spectator ion that is the ion which does not react because it is present before and after the reaction
When these ions are removed, the ionic equation is called the net ionic equation
For gases and solids including water (H₂O) can be written as an ionized molecule
Reaction
CuSO₄(aq)+Na₂S(aq)⇒CuS(s)+Na₂SO₄
ionic equation
Cu²⁺(aq)+SO₄²⁻(aq)+2Na⁺(aq)+S²⁻(aq)⇒CuS(s)+2Na⁺(aq+SO₄²⁻(aq)
spectator ions : 2Na⁺ and SO₄²⁻
Net ionic equation
Cu²⁺(aq)+S²⁻(aq)⇒CuS(s)
<u>Answer:</u> The additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
<u>Explanation:</u>
To calculate the mole percent of a substance, we use the equation:

Mass percent means that the mass of a substance is present in 100 grams of mixture
To calculate the number of moles, we use the equation:

We require the molar masses of Z and X to calculate the mole percent of Z and X respectively
Hence, the additional information that is helpful in calculating the mole percent of XCl(s) and ZCl(s) is the molar masses of Z and X
Since it is stated that nitrogen is the limiting reactant (sometimes called limiting reagent), you only have to worry about the amount of nitrogen since we know that there is excess silicon.
Since this is a stoichiometry question, the first thing to do is turn the mass of nitrogen gas into moles by dividing the mass of nitrogen gas by its molar mass. (14.33g)/(28g/mol)=0.5118mol nitrogen gas. Then you have to convert moles of nitrogen gas to moles of silicon nitride by using the fact that 2 moles of nitrogen gas turn into 1 mole of silicon nitride (i got that ratio from the chemical equation given). (0.511mol N₂)x(1mol Si₃N₄/2mol N₂)=0.2555mol Si₃N₄. Know you just need to find the mass of silicon nitride by multiplying the number of moles of silicon nitride by its molar mass. (0.2555mol)x(140g/mol)=35.85g
Therefore the amount of silicon nitride produced from this reaction 35.85g.
I hope this helps