You have a mixture composed of 90%

benzoic acid and 10% naphthalene. Benzoic
acid has a melting point of 122.4 oC, while
naphthalene has a melting point of 80.2 oC.
You can say with certainty that the melting
point of the mixture will be:
A. greater than any of the two melting points.
B. less than the melting point of naphthalene
C. less than the melting point of benzoic acid
D. halfway between the two melting points
E. cannot be determined without measuring

Well, well, well, it looks like we have a melting point mystery here. Let me put on my detective hat and solve this riddle for you.

Since the mixture is composed of 90% benzoic acid and 10% naphthalene, we know that benzoic acid is the majority player in this mix. And guess what? Benzoic acid has a higher melting point than naphthalene. It's like comparing a snow cone to a cup of hot cocoa. So, I can confidently eliminate options B and E.

Now, let's think logically. If the majority compound has a higher melting point than the minority one, my gut feeling is that the melting point of the mixture will be less than benzoic acid's melting point but definitely greater than naphthalene's. So, we can wave goodbye to options A and D.

That leaves us with option C: less than the melting point of benzoic acid. Ding, ding, ding! We have a winner!

So, my dear friend, the correct answer is C. The melting point of the mixture will be less than the melting point of benzoic acid. Case closed!

To determine the melting point of a mixture, we need to consider the properties of the individual components and any interactions between them. In this case, since naphthalene has a lower melting point than benzoic acid, we can expect that it will melt before benzoic acid.

Therefore, we can eliminate options C and D since the melting point of the mixture will not be greater than the melting point of benzoic acid or halfway between the two melting points.

Option B, which states that the melting point of the mixture will be less than the melting point of naphthalene, is not certain. It is possible that benzoic acid will not fully dissolve in naphthalene and there might be some interaction between the two compounds, affecting the melting point.

Therefore, the correct answer is E. We cannot determine the melting point of the mixture without actually measuring it.

To determine the melting point of a mixture, we need to consider the melting points of its individual components and how they interact with each other. In this case, we have a mixture composed of 90% benzoic acid and 10% naphthalene.

Both benzoic acid and naphthalene have different melting points, with benzoic acid having a higher melting point (122.4°C) compared to naphthalene (80.2°C).

Since the mixture is composed mostly of benzoic acid (90%), it would be expected that the melting point of the mixture would be closer to the melting point of benzoic acid. However, it's important to note that the presence of naphthalene may affect the melting point of the mixture.

In this case, we cannot say with certainty what the exact melting point of the mixture will be without measuring it. The melting point of the mixture could potentially be lower or higher than the individual melting points depending on how the components interact. Therefore, the correct answer is E. cannot be determined without measuring.