Answer:
pH of resulting solution = 7.98
Explanation:
The balanced equation
HA + NaOH - Na+ + A- + H2O
Number of moles of A = Number of moles of HA = Number of moles of NaOH
= 35.8/1000 * 0.020 = 0.000716 mol
Initial concentration of A = 0.000716/0.0608 = 0.01178 M
pKb = 14 – pKa = 14 -3.9 = 10.1
Kb = 10^{-Kb} = 10^{-10.1} = 7.943 * 10^-11
Kb = [HA][OH-]/[A-]
Kb = a^2/(0.01178 -a) = 7.943 * 10^-11
a^2 + 7.943 * 10^-11 a – 9.357 * 10^-13 = 0
a = 9.673 * 10^-7
OH- = a = 9.673 * 10^-7 M
pOH = -log [OH-] = -log (9.673 * 10^-7) = 6.02
pH = 14-6.02 = 7.98
What? It would be nice if you show pic
1) Atomic number of magnesium (Mg) is 12, it means that it has 12 protons and 12 electrons.
Electron configuration of magnesium atom: ₁₂Mg 1s² 2s² 2p⁶ 3s².
2) Atomic number of aluminium (Al) is 13, it means that it has 13 protons and 13 electrons., but if it lost one electron, it will have 12 electrons and 13 protons and become aluminium cation Al⁺.
Electron configuration of aluminium cation: ₁₃Al⁺ 1s² 2s² 2p⁶ 3s².
3) Atomic number of silicon (Si) is 14, it means that it has 14 protons and 14 electrons., but if it lost two electrons, it will have 12 electrons and 14 protons and become silicon cation Si²⁺.
Electron configuration of silicon cation: ₁₄Si²⁺ 1s² 2s² 2p⁶ 3s².
Answer : The amount of carbon dioxide produced is, 197.12 grams.
Explanation : Given,
Moles of ethanol = 2.24 mole
Molar mass of carbon dioxide = 44 g/mole
The balanced chemical reaction will be,

First we have to calculate the moles carbon dioxide.
From the balanced chemical reaction, we conclude that
As, 1 mole of ethanol react to give 2 moles of carbon dioxide
So, 2.24 mole of ethanol react to give
moles of carbon dioxide
Now we have to calculate the mass of carbon dioxide.


Therefore, the amount of carbon dioxide produced is 197.12 grams.
Answer:
The answer to your question is letter A
Explanation:
Abundance Atomic mass
V-50 0.25% 49.947
V-51 99.750% 50.944
Formula
Average atomic mass = [V-50-Abundance x V-50-Atomic mass] +
[ V-51-Abundance x V-51-Atomic mass]
Substitution
Average atomic mass = [ 0.0025 x 49.947] + [0.9975 x 50.944]
= 0.125 + 50.817
Result
= 50.942 amu