Answer:
Au
Explanation:
For the density of a face-centered cubic:

where
= molar mass of the compound
avogadro's constant
the volume of a unit cell
Given that:
Density
= 19.30 g/cm³
a = 0.408 nm
a = 
a = 
∴



Thus, the molar mass of 197.37 g/mol element is Gold (Au).
The concentration of Ca2+ ions is half that of the Cl- ions.
I believe that the answer is A, continental-continental.
Stratosphere:) hope this helped
Answer:
True
Explanation:
It's true because the pH is a measure of how basic or acid a solution is. In an acidic medium, the pH scales goes from 0 to 7. While in a basic medium goes from 7 to 14. The lower the pH value of the most acid the solution is.
1. The expression pH = -log(molar concentration of hydronium) allow to calculate the pH of a solution.
2. On the other hand, the expression pOH = -log(molar concentration of hydroxide) allow to determine the pOH of a solution.
The values of pH and pOH always obey the following expression:
pH + pOH = 14
Thus if for instance the pH becomes smaller the pOH must become bigger in order to fulfill the equation. Which means that the concentration of hydronium ions is greater than the hydroxide concentration.
For example, in an acidic medium:
if pH= 3, pOH= 11
In this case the molar concentration of hydronium is 0,001M. And the molar concentration of hydroxide ions is just 0,00000000001M.