Answer:
He needs to add 4 mL of the 0.5 M solution to 6 mL of water.
Answer:
potassium
The third alkali metal is K (potassium). The atomic number of K (potassium) is 19. Thus, the atomic number of third alkali metal is 19
Explanation:
We assume that we have Ka= 4.2x10^-13 (missing in the question)
and when we have this equation:
H2PO4 (-) → H+ + HPO4-
and form the Ka equation we can get [H+]:
Ka= [H+] [HPO4-] / [H2PO4] and we have Ka= 4.2x10^-13 & [H2PO4-] = 0.55m
by substitution:
4.2x10^-13 = (z)(z)/ 0.55
z^2 = 2.31x 10^-13
z= 4.81x10^-7
∴[H+] = 4.81x10^-7
when PH equation is:
PH= -㏒[H+]
= -㏒(4.81x10^-7) = 6.32
How many protons does Thorium have? 90
How many neutrons does Thorium-234 have? 144
Calculate the mass defect for the isotope thorium-234 1.85864 amu
