There are two isotopes of uranium abundant in nature
U235 and U238
As given that the sample has average molar mass of 237.482 amu
Let the amount of U235 in 100g sample = x
the amount of U238 in 100 g sample = 100-x
the average molar mass = [235(x) + 238 (100-x)] / 100
237.482 = [235(x) + 238 (100-x)] / 100
237.482 X 100 = [235(x) + 238 (100-x)]
23748.2 = 235 x + 23800 - 238x
51.8 = 3x
x = 17.27 g
So percentage of U-235 = 17.27 %
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.
Answer:yes they do represent
The number of protons among the 2 isotopes remain the same, what varies is the number of neutrons between the 2 isotopes. The isotope with the larger mass number possess a greater number of neutrons compared to the other one.