E- is a negative electron
Answer is: pH value of solution of NaC₂H₃O₂ is 9.07.
Chemical reaction: C₂H₃O₂⁻ + H₂O ⇄ HC₂H₃O₂ + OH⁻.
Ka(HC₂H₃O₂) = 1,8·10⁻⁵.<span>
Ka · Kb = Kw.
</span>1,8·10⁻⁵ mol/dm³ · Kb = 1·10⁻¹⁴ mol²/dm⁶; the ionic product of water at 25°C.<span>
Kb(</span>C₂H₃O₂⁻)
= 1·10⁻¹⁴ mol²/dm⁶ ÷ 1,8·10⁻⁵ mol/dm³.<span>
Kb(</span>C₂H₃O₂⁻) =
5,56·10⁻¹⁰ mol/dm³.
c(C₂H₃O₂⁻) = 0,25 M.
[OH⁻] = [HC₂H₃O₂] = x.
[C₂H₃O₂⁻] = 0,25 M - x.
Kb = [OH⁻] · [HC₂H₃O₂] / [C₂H₃O₂⁻].
5,56·10⁻¹⁰ = x² / (0,25 M -x).
Solve quadratic equation: x = [OH⁻] = 0,0000118 M.
pOH = -log[OH⁻] = -log(0,0000118M) = 4,93.
pH + pOH = 14.
pH = 14 - 4,93 = 9,07.
The chemical formula : 3HgBr₂(Mercury(II) bromide)
<h3>Further explanation</h3>
Given
The chemical formulas of Mercury and Bromine
Required
The appropriate chemical formula
Solution
A molecular formula is a formula that shows the number of atomic elements that make up a compound.
The number of molecules is determined by the coefficient in front of the compound
the number of atoms is determined by the subscript after the atom and the coefficient
Three molecules⇒ coefficient = 3
one atom of Mercury ⇒Hg
two atoms of Bromine ⇒ Br₂
The chemical formula : 3HgBr₂
Answer:
(B) F⁻, HCOOH
Explanation:
(A) CH₄, HCOOH
(B) F⁻, HCOOH
(C) F⁻, CH₃-O-CH₃
The hydrogen bonds are formed when the hydrogen is found between two electronegative atoms such as oxygen (O), nitrogen (N) or florine (F).
O····H-O, F····H-O, O····H-N
(A) CH₄, HCOOH
- here methane CH₄ is not capable to form hydrogen bond with water
- formic acid HCOOH can form hydrogen bonds with water
H-C(=O)-O-H····OH₂
(B) F⁻, HCOOH
-both floride (F⁻) and formic acid can form hydrogen bonds with water
F····OH₂
H-C(=O)-O-H····OH₂
(C) F⁻, CH₃-O-CH₃
- dimethyl-ether CH₃-O-CH₃ is not capable to form hydrogen bond with water
- floride (F⁻) can form hydrogen bonds with water
F····OH₂
Answer:
The change was physical, meaning it went from liquid to solid, or the other way around.
Explanation: