Refer to the table below.Use charge balance to determine the value of x in the pyrosilicate Ba_xSi₂O₇. Table 23.2 Types of Silicate Structures

Question

Quizplus · Accepted Answer

In pyrosilicate structures, charge balance requires that the sum of the cation charges be equal to the sum of the anion charges. 
On the cation side, we have Ba^(2+) + S^(2-) = 0.
On the anion side, we have 2Si^(4-) + xB^(3-) + 17O^(2-) = 0.
Simplifying the equation: 2(-4) + 3x(-3) + 17(-2) = 0
-8 - 3x + (-34) = 0
-3x = 42
x = -14/(-3) = 4.67
Since x must be a whole number representing the ratio of boron to silicon ions, the closest answer choice is 3.

Refer to the Table Below