To determine which substance will form a solution when mixed with liquid benzene ([tex]\( \text{C}_6\text{H}_6 \)[/tex]), we need to consider the principle "like dissolves like". This principle states that substances with similar polarity are likely to dissolve in each other.
Let's analyze each of the given substances in terms of their polarity:
- A. [tex]\( \text{MgF}_2(s) \)[/tex]:
- Magnesium fluoride ([tex]\( \text{MgF}_2 \)[/tex]) is an ionic compound. Ionic compounds generally have strong ionic bonds and are typically soluble in polar solvents, such as water. Benzene is non-polar, so [tex]\( \text{MgF}_2 \)[/tex] is not likely to dissolve in benzene.
- B. [tex]\( \text{I}_2 \)[/tex]:
- Iodine ([tex]\( \text{I}_2 \)[/tex]) is a non-polar molecule. Non-polar substances usually dissolve well in non-polar solvents. Since benzene is non-polar, [tex]\( \text{I}_2 \)[/tex] will readily dissolve in benzene.
- C. [tex]\( \text{H}_2\text{O} \)[/tex]:
- Water ([tex]\( \text{H}_2\text{O} \)[/tex]) is a highly polar molecule. Polar substances tend to dissolve in polar solvents. Since benzene is non-polar, [tex]\( \text{H}_2\text{O} \)[/tex] will not dissolve well in benzene.
- D. [tex]\( \text{HCl}(g) \)[/tex]:
- Hydrogen chloride ([tex]\( \text{HCl} \)[/tex]) is a polar molecule when dissolved in water or when in gaseous form. Polar substances like [tex]\( \text{HCl} \)[/tex] are not likely to dissolve in non-polar solvents such as benzene.
Based on this analysis, the substance that will form a solution when mixed with liquid benzene ([tex]\( \text{C}_6\text{H}_6 \)[/tex]) is:
B. [tex]\( \text{I}_2 \)[/tex]
