Respuesta :
The concentration is expressed in molarity which is equal to moles of solute per liters of solution. We use this definition to calculate the amount we need of the solute. We do as follows:
0.200 mol ca(no3)2 / L solution (0.250 L solution ) = 0.05 mol ca(no3)2
0.05 mol ca(no3)2 (164.09 g/ mol) = 8.20 g ca(no3)2 needed
0.200 mol ca(no3)2 / L solution (0.250 L solution ) = 0.05 mol ca(no3)2
0.05 mol ca(no3)2 (164.09 g/ mol) = 8.20 g ca(no3)2 needed