The molarity is a concentration unit which defined as the number of moles of solute divided by the number of liters of solution. So the molarity of the solution is 3/2=1.5 mol/L.
Number 4 is
-Oxidation occurs at the anode, while reduction occurs at the cathode. Recharging a battery involves the conversion of electrical energy to chemical energy. During recharging, there is movement of electrons from an external power source to the anode, and on the other side electrons are removed from the cathode.
No doubt it's B. solid, liquid, and gas.
Hope this helps!
