Question

Barium reacts with a polyatomic ion to form a compound with the general formula Ba3(X)2. What would be the most likely formula for the compound formed between sodium and the polyatomic ion X?
A. NaX
B. Na2X
C. Na2X2
D. Na3X
E. Na3X2

Answer 1

Answer:

Na3X  (Option Dis correct)

Explanation:

Ba + X → Ba3(X)2

Barium has an oxidation number of +2 = Ba^2+

Barium will form the compound Ba3(X)2 when it reacts with X

Ba3(X)2 = 3Ba^2+ + 2X^3-

X should be an element with oxidation number -3

When sodium will bind with X the following reaction will happen:

3Na+ + X^3- = Na3X

Since sodium has only 1 valence electron, we need 3 sodium atoms to bind 1 X atom.

Option D Na3X is correct

Answer 2

Answer:

D. Na₃X

Explanation:

We have the neutral compound Ba₃(X)₂. The total charge (zero) is equal to the sum of the charges of the ions times the number of ions in the molecule.

3 × qBa + 2 × qX = 0

3 × (+2) + 2 × qX = 0

2 × qX = -6

qX = -3

If we have the cation Na⁺ and X³⁻, a neutral molecule would require 3 Na⁺ and 1 X³⁻. The resulting compound is Na₃X.