Question

What is the molarity of a solution prepared by dissolving 198 g of BaBr2 in 2.00 liters of solution?

Answer 1

The molarity of the solution is 0.335
`(moles)/(liter)`

Step-by-step explanation:

Molar concentration is a measure of the concentration of a solute in a solution, be it some molecular, ionic, or atomic species.

Molarity is the number of moles of solute that are dissolved in a certain volume and is calculated by:

`Molarity=(number of moles of solute)/(volume)`

Molarity is expressed in units
`(moles)/(liter)`.

Being the molar mass of BaBr2 equal to 297.14 g/mole, that is to say that 1 mole contains 297.14 grams, the mass of 198 grams are contained in:

`198 grams*(1 mole)/(297.14 grams) = 0.67 moles`

So:

• number of moles of solute= 0.67 moles
• volume= 2 L

Replacing in the definition of molarity:

`Molarity=(0.67 moles)/(2 L)`

Solving:

Molarity= 0.335
`(moles)/(liter)`

The molarity of the solution is 0.335
`(moles)/(liter)`