Among the choices, the polyatomic ion is only the third choice, NH4+ where it is composed of nitrogen one atom of nitrogen and 4 atoms of hydrogen. Choice 2 is a monoatomic atom being composed only of calcium. Then, the first and fourth choices are not ions because they are not charged.
Answer:
The answer is "3.57 and 0.07".
Explanation:
Using the slop formula:

Given:
length path
from calibration it is found that

Answer:
A high pH value indicates a high concentration of OH- ion
Explanation:
The higher the OH- ion concentration high will be the pH.In simple words if the concentration of OH- ions are increased then the pH of the solution will also increase which means the solution will turns towards basic with increasing its OH- ion concentration.
Let us assume that the OH- concentration of a solution is 10-9 so the pOH of that solution will be 9 and the pH will be 5.
Now the concentration of OH-ion of that solution is increased from 10-9 to 10-8 now the pOH of that solution is 8 and the pH is 6.
The substance would be referred to as a compound substance.