Molarity = moles of solution/ liter of solution
4.32x10^2/20
432/20=
21.6 M
i believe
2 g/mL
good luck!
Answer:
The answer to your question is 0.269 g of Pb
Explanation:
Data
Lead solution = 0.000013 M
Volume = 100 L
mass = 0.269 g
atomic mass Pb = 207.2 g
Chemical reaction
2Pb(s) + O₂(aq) + 4H⁺(aq) → 2H₂O(l) + 2Pb₂⁺(aq)
Process
1.- Calculate the mass of Pb in solution
Formula
Molarity = 
Solve for number of moles
Number of moles = Volume x Molarity
Substitution
Number of moles = 100 x 0.000013
Number of moles = 0.0013
2.- Calculate the mass of Pb formed.
207.2 g of Pb ----------------- 1 mol
x g ----------------- 0.0013 moles
x = (0.0013 x 207.2) / 1
x = 0.269 g of Pb
Answer: The atomic weight of silver is 107.87 amu
Explanation:
Mass of isotope silver-107 = 106.91 amu
% abundance of isotope silver -107 = 51.84% = 
Mass of isotope silver-109 = 108.90 amu
% abundance of isotope silver-109 = 48.16% = 
Formula used for average atomic mass of an element :

![A=\sum[(106.91\times 0.5184)+(108.90\times 0.4816)]](https://tex.z-dn.net/?f=A%3D%5Csum%5B%28106.91%5Ctimes%200.5184%29%2B%28108.90%5Ctimes%200.4816%29%5D)

Thus atomic weight of silver is 107.87 amu