Respuesta :
Answer: 3= Na
Explanation:
Ok, let us check one or two definitions before answering the question above.
WHAT IS THE MEANING OF EXCESS REACTANT? :Excess Reactant is the Reactant that remains in the Chemical reaction after the limiting Reactant has been used completely.
WHAT IS THE MEANING OF LIMITING REACTANT: limiting Reactant is the Reactant that will be used up completely before the excess Reactant in a chemical reaction.
So, bearing those explanation on mind, let us answer this equation. From the question, we are given that we have 20.5 grams of chlorine,Cl and 20.5 grams of sodium. The balanced equation of reaction is given below;
2Na + Cl2 --------------------> 2NaCl.
2 moles of sodium react with one mole of Chlorine to give one mole of Sodium Chloride.
Hence, we know that the number of moles,n= mass/molar mass.
So, the number of moles for 20. 5 grams of Chlorine= 20.5 g/(35.5 ×2).
Number of moles of Chlorine= 20.5g/ 71(gram per mol).
Number of moles of Chlorine= 0.29 moles.
For Sodium; 2 moles of sodium is used in the reaction. So,the number of moles of sodium,n= 20.5/23 (gram per mole) = 0.89 moles.
So, judging from the number of mole, Sodium with the highest number of moles is the EXCESS REACTANT and Chlorine is the LIMITING REAGENT.
The number of moles of Sodium required is 2moles of Sodium × 0.29 moles= .58 moles