A temperature change in a reaction indicates a chemical change
They are all metals that share common structures and similar properties that meant them appear identical to one another
Answer: 0.25M
Explanation: Because of the highest concentration of water and, if they are all the same volume, the greatest amount of water assuming it is a solid solute in a water solution.
The amount of the solute is constant during dilution. So the mole number of HCl is 2*1.5=3 mole. The volume of HCl stock is 3/12=0.25 L. So using 0.25 L stock solution and dilute to 2.0 L.
