Question

What is the molarity of 16.1 grams of lithium hydroxide Dissolved to 200.0 mL of solution?

Here's what I tried:

LiOH 16.1g / 23.95 g/mol= 0.67mol

200ml= 0.2L

0.67mol / 0.2L= 3.36

but my answer is wrong....and I don't know why?

Answer 1

Molarity is defined as the number of moles of solute present in one litre of solutions

i.e Molarity = moles of solute( LiOH)/ volume of Sol. in liter

Here mass of LiOH is given 16.1g we have to find moles.so we divide it by its molar mass which is 23.95 g/mol

So moles= 16.1g÷23.95g/mol = 0.67 mol

Now.l,

Converting volume 200 ml to litre i.e 0.2 L

For molarity we have to divide moles of LiOH with volume of Sol.

Molarity =( 0.67÷0.2 ) mol/L = 3.3 mol/L

Your answer is correct, but if you consider correct significant figures it should be 3.3 mol/L. Also try to give Answer in proper units.

answered by: anonymous