The relationship between the Van't Hoff factor ($i$), the degree of dissociation ($\alpha$), and the number of ions produced per formula unit ($n$) is given by the formula: $i = 1 + (n - 1)\alpha$

1. Identify $n$: Barium nitrate dissociates as: $Ba(NO_3)_2 \rightarrow Ba^{2+} + 2NO_3^-$. Total ions ($n$) = $1 + 2 = 3$.

2. Substitute values: Given $i = 2.74$. $2.74 = 1 + (3 - 1)\alpha$

• $2.74 = 1 + 2\alpha$

3. Solve for $\alpha$: $2\alpha = 2.74 - 1$ $2\alpha = 1.74$

• $\alpha = \frac{1.74}{2} = 0.87$

4. Convert to percentage:

• Percentage degree of dissociation = $0.87 \times 100\% = 87\%$.