70.306 would be your answer.
I think the answer would be Ionic sodium phosphate (Na3PO4) because it has the greatest boiling point elevation.
A substance can dissolve in another when they have thee same type of intermolecular interaction.
<h3>What is solubility?</h3>
The term solubility of a solute refers to the extent to which a solute dissolve in a solvent. We must know that a substance can dissolve in another when they have thee same type of intermolecular interaction.
Thus;
a) Octane (C8H18) mixes well with CCl4 because they are both non polar substances.
b) Methanol (CH3OH) is mixed with water in all ratios because the both are polar substances.
c) NaBr dissolves very poorly in acetone (CH3 ― CO ― CH3) because acetone is only slightly polar.
Learn more about solubility:brainly.com/question/8591226
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