isn't concentration = molarity?

[joonkimdds]

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I thought concentration means Molarity, which is mol of solute / L of solution.

But then I thought about "concentration of water" and that doesn't sound right because water is solvent, not solute.


And also, when the problem gives me mol of H, it asked me to find pH.
pH = -log[H], and [H] is Molarity of H or concentration of H.
But it didn't give me L of solvent, but it just either assumed that there is 1L or it just used mol of H and called it [H].

I am confused.

 

[batch5000]

Molarity is just one measure of concentration. Pressure is also sometimes thought of as a concentration when solving equations involving gas. The molarity of water is approximately 55 M. I know it is weird, but just think of it as the number of moles of water in 1 L pure water.

 

[batch5000]

If you have the concentration of H+, then you don't need to know the volume that you are dealing with to find pH. Simply use pH = - log [H]. It doesn't matter what your volume is because the bracket notation always assumes 1 L anyway.