Out of the options, the best indicator is a color change since it is the only one that can't really be blamed on a physical change. you will eventually notice that during qualitative labs and some quantitative labs, usually the thing that you are looking for is either color change or the production of a precipitate to indicate the presence of a chemical reaction
I think that it's cannot include supernatural explanations, or C.
If i got it wrong sorry
Answer:
[Ar] 3d10 4s2 4p3 is shorthand, 1s22s22p63s23p63d104s24p3 long hang
Explanation:
The shorthand is made using the lowest & closest noble gas, and picking up where it leaves off as follows, and longhand is made from a followed pattern you can easily find
<u>Answer:</u> The concentration of solute is 0.503 mol/L
<u>Explanation:</u>
To calculate the concentration of solute, we use the equation for osmotic pressure, which is:

where,
= osmotic pressure of the solution = 24 atm
i = Van't hoff factor = 2 (for NaCl)
c = concentration of solute = ?
R = Gas constant = 
T = temperature of the solution = ![25^oC=[273+25]=298K](https://tex.z-dn.net/?f=25%5EoC%3D%5B273%2B25%5D%3D298K)
Putting values in above equation, we get:

Hence, the concentration of solute is 0.503 mol/L