Answer: The layers are ordered by density, with the least dense layer on top, and the densest layer on the bottom.
Explanation:
Plato
Voltmeter is the device that is used to measure the potential difference across the battery.
<h2>What are the usage of voltmeter?</h2><h3 /><h3>Usage of Voltmeter</h3>
Voltmeter is an instrument that measures voltages of both direct and alternating electric current. On a scale of voltmeter usually graduated in volts, millivolts (0.001 volt), or kilovolts (1,000 volts).
Voltmeter is connected in parallel form. It has a high resistance so that it takes negligible current from the circuit so we can conclude that Voltmeter is the device that is used to measure the potential difference across the battery.
A is obviously out because it leads to a volume of 125.0 milliliters of the new solution and gives you a lower concentration than you were aiming for.
D is out because you are adding 75 milliliters of the stock solution, so your concentration would be too high. You only need 25.0 milometers of stock solution per 100 milliliters of the new solution.
C is also out because it leads to 50.0 milliliters stock solution per 100 milliliters of the new solution and hence the wrong concentration.
B is by default the correct answer. It also details the correct technique. First you add the stock solution (This you know from your calculations to be 25 milliliters.) then you add the water up to the volume you needed. (Because the calculations only tell you the total volume of water not what you need to add) You also add the water last so you can rinse the neck of the flask to make sure you also get all the stock solution residue into the stock solution.
I would add the final step of stirring, but B is the only answer that can be correct.
