How many moles of Ba(OH)2 are present in 205 mL of 0.400 M Ba(OH)2​

0.082 moles

Explanation:

To answer this question we'll need to use the definition of molarity:

We are given the molarity and mililiters, so now we convert 205 mL into L:

Now we can calculate the number of moles:

0.400 M = moles / 0.205 L

yes the answer is total mass in unchanged   : )