Molarity Question

[Mariolee]

I suck at molarity and moles which seems incredibly simple but I struggle with it a lot for some reason.

This question I came upon some review tripped me up a lot:

What has greater molarity: 2 mols of sodium dissolved in 1L of water or 2 mols of glucose dissolved in methanol?

A. Sodium in water
B. Glucose in methanol
C. Both are equal
D. Cannot be determined

The correct answer is Both are equal but I put D because they never told us how much methanol the glucose was dissolved in and I thought molarity had a lot to do with the amount of solvent? Could someone please help explain? Thank you?

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[swollcat]

I suck at molarity and moles which seems incredibly simple but I struggle with it a lot for some reason.

This question I came upon some review tripped me up a lot:

What has greater molarity: 2 mols of sodium dissolved in 1L of water or 2 mols of glucose dissolved in methanol?

A. Sodium in water
B. Glucose in methanol
C. Both are equal
D. Cannot be determined

The correct answer is Both are equal but I put D because they never told us how much methanol the glucose was dissolved in and I thought molarity had a lot to do with the amount of solvent? Could someone please help explain? Thank you?

I said C at first glance. The question is somewhat poorly worded, but you can infer the concept they're trying to test and it is't to catch you sleeping on semantics. 2 mols of a substance in 1L of solution is 2M not matter how you spin it. They're banking on you incorrectly assuming that a compound like glucose has more moles than simple sodium.

 

[Mariolee]

I said C at first glance. The question is somewhat poorly worded, but you can infer the concept they're trying to test and it is't to catch you sleeping on semantics. 2 mols of a substance in 1L of solution is 2M not matter how you spin it. They're banking on you incorrectly assuming that a compound like glucose has more moles than simple sodium.

The thing I'm confused about however is that we didn't know if there was only one liter of methanol, unless I missed something.

 

[Roflcoppter1337]

Molarity is simply moles of solute per liter of solution. It does not matter what the solute or solvent is. You should assume there is 1L methanol based on the question. They're simply testing if you understand what molarity is. Don't overthink it.