Answer: One formula unit of NaCl consists of one cation, whose chemical symbol is
and one anion whose chemical symbol is 
Explanation:
For formation of a neutral ionic compound, the charges on cation and anion must be balanced. The cation is formed by loss of electrons by metals and anions are formed by gain of electrons by non metals.
The cation is formed by the metal sodium which forms
and the anion is formed by non metal chlorine which forms
.
For a formula unit of sodium chloride, the charges have to be balanced , thus the valencies of ions are exchanged and the neutral compound result. Thus
and
combine to form neutral 
The color it produces is Bright green.
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.
Answer:Most elements on the periodic table are metals. Looking at the periodic table shows that most elements are metallic.
Explanation: Sorry if this want what you were looking for