<p>This is a Roman-numeral true/false question from Kaplan.</p>
<ol>
<li>Which of the following statements about boiling-point elevation is NOT true?</li>
</ol>
<p>II. The molal concentration of solute particles dissolved in the solvent is an important factor in determining the molal boiling-point elevation constant.</p>
<p>According to the answer key, II is not the correct answer (meaning that the statement is true). But isn't the boiling-point elevation constant (Kb) independent of the concentration? Did they mean to say that molality is an important factor in determining the boiling-point elevation?</p>
<p>Thanks.</p>
<p>Okay, I have another question. I’m sorry to double-post; I couldn’t find a way to edit my original post.</p>
<p>In the same book, the answer explanation for #36 on Practice Test 2 reads: “Electronegativity increases in going from the lower left to the upper right of the Periodic Table, excepting the noble gases. So all you need to do here is locate the answer choices in the Periodic Table and find the one that is the closest to the upper right-hand corner and is not a noble gas.”</p>
<p>On Practice Test 3, the explanation for #18 reads: “Ionization energy tends to increase from left to right across a row in the Periodic Table; neon has the highest ionization energy of the elements in the second row.”</p>
<p>Hello?! These answers cannot both be right, but I’ve scoured the Internet and found much contradictory information. Can anyone here help? Noble gases are NOT assigned electronegativity values, right?</p>
<p>This is my understanding of the topic: boiling point elevation (and its constant) is a colligative property, which is dependent on the number/concentration of solute particles, not their identities. Therefore, II would be true.</p>
<p>Electronegativity is not the same thing as ionization energy. I don’t quite see how those statements contradict each other.</p>
<p>Oh, lord. Sorry about the EN/IE question. I got absolutely no sleep last night, can you tell? This is so embarrassing…sigh.</p>
<p>Ahem. Anyway…</p>
<p>But the constant doesn’t depend on the number of solute particles. You can look up water’s boiling-point elevation constant in a table, and it’s the same regardless of the identity or concentration of the solute. Boiling-point elevation is a colligative property, but the boiling-point elevation constant is…constant. Right?</p>
<p>Yes, I’m pretty sure you’re right on the molality/boiling point elevation question. The boiling point elevation constant for water is something like .51 degrees/molals of solute no matter what.</p>