So I'm getting ready for a final exam and going over some homework, and I found a problem I'm not sure how to solve. I thought I got the answer originally but it's marked wrong. Here it is:
Calculate the molarity of a solution made with 4.00 g of NaOH in 100 mL of water.
I thought the formula for molarity was moles of the solute over liters of the solution. So I converted 4g of NaOH to 0.1 moles of NaOH. Then I converted the 100 mL to 0.1 L. Finally, I divided them.
0.1 mol / 0.1 L
And of course that equals 1. That's marked wrong though... Any advice?
Calculate the molarity of a solution made with 4.00 g of NaOH in 100 mL of water.
I thought the formula for molarity was moles of the solute over liters of the solution. So I converted 4g of NaOH to 0.1 moles of NaOH. Then I converted the 100 mL to 0.1 L. Finally, I divided them.
0.1 mol / 0.1 L
And of course that equals 1. That's marked wrong though... Any advice?
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Sig figs maybe? see if the 100 mL of water has a decimal at the end. Then it would require 3 sig figs
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The correct answer is 1 mol/L.