Question

What is the empirical formula of an unknown substance with 1.53g of Na and 2.36g of Cl?

a) NaCl₂
b) Na₂Cl
c) NaCl
d) Na₃Cl₂

Answer 1

After converting the given mass of Na and Cl to moles, we find that the mole ratio of Na to Cl is 1:1, indicating that the empirical formula of the substance is NaCl (option c).

Step-by-step explanation:

To determine the empirical formula of an unknown substance with 1.53g of Na and 2.36g of Cl, we start by converting the masses of the elements to moles. Using the atomic masses (Na: 22.99 u, Cl: 35.45 u), we have:

• 1.53g Na ÷ 22.99g/mol = 0.066 moles of Na
• 2.36g Cl ÷ 35.45g/mol = 0.066 moles of Cl

Since the mole ratio of Na to Cl is 1:1, the empirical formula is NaCl.