<u>We are given:</u>
Mass of Na added = 4.35 grams
Mass of water = 105 grams
<u>Mass Percent of Na:</u>
Total mass of the solution = mass of solute + mass of solvent
Total mass of the solution = 4.35 + 105 = 109.35 grams
Mass percent of solute = (mass of solute / mass of solution) * 100
Mass percent of Solute = (4.35 / 109.35) * 100
Mass percent = 3.978 %
If 1mole ------------- is ---------------- 6.02*10²³
than 0.25mole ----- is ---------------- x
x = [0.25mole*6.02*10²³]/1mole = <u>1,505*10²³</u>
**Visible confusion** no problem
Answer:
See explaination
Explanation:
The invariant mass of an electron is approximately9. 109×10−31 kilograms, or5. 489×10−4 atomic mass units. On the basis of Einstein's principle of mass–energy equivalence, this mass corresponds to a rest energy of 0.511 MeV.
Check attachment for further solution to the exercise.