Respuesta :
HClO is a weak acid, which means the ions do not fully dissociate. The hydrolysis reaction for the hypochlorous acid is:
HClO + H2O ⇄ H3O+ +OCl-
Then the equilibrium constant, Ka, of dilute HClO would be:
[tex] K_{a} = \frac{[ H_{3} O^{+} ][O Cl^{-} ]}{HClO} [/tex]
Then we do the ICE table. I is for the initial concentration, C for the change and E for the excess.
HClO + H2O ⇄ H3O+ + OCl-
I 1.0x10^-4 0 0
C -x +x +x
E (1.0x10^-4 - x) x x
Substituting the excess (E) concentration to the Ka equation:
[tex]K_{a} = \frac{[x ][x]}{1.0 \ x \ 10^{-4} - x }[/tex]
Simplifying the equation would yield a quadratic equation:
[tex] x^{2} + K_{a}x-(1.0 \ x \ 10^{-4}) K_{a}=0 [/tex]
The Ka for HClO is an experimental data which was determined to be 2.9 x 10^-8. Substitute this to the equation, determine the roots, then you get the value for x, which is the concentration of H3O+ and ClO-. Just use your calculator feature Shift-Solve.
x = 1.688 x 10^-6 M = [H3O+] = [ClO-]
Then, you can determine the conc of [OH-] through pH.
pH = -log {H3O+] = -log [1.688 x 10^-6] = 5.77
pOH = 14 - pH = 14 - 5.77 = 8.23
pOH = 8.23 = -log [OH-]
[OH-] = 5.89 x 10^-9 M
Also, since HClO is (1.0x10^-4 - x), then it's concentration would be:
[HClO] = 1.0x10^-4 - 1.688 x 10^-6 = 9.83 x10^-5 M
Let's summarize all concentrations:
[HClO] = 9.83 x10^-5 M
[OH-] = 5.89 x 10^-9 M
[H3O+] = [ClO-] = 1.688 x 10^-6 M
Since the solution is dilute, H2O is relatively higher in concentration.
Thus in relative amounts, the order would be
H2O >>> HClO > H3O+ = ClO- > OH-
HClO + H2O ⇄ H3O+ +OCl-
Then the equilibrium constant, Ka, of dilute HClO would be:
[tex] K_{a} = \frac{[ H_{3} O^{+} ][O Cl^{-} ]}{HClO} [/tex]
Then we do the ICE table. I is for the initial concentration, C for the change and E for the excess.
HClO + H2O ⇄ H3O+ + OCl-
I 1.0x10^-4 0 0
C -x +x +x
E (1.0x10^-4 - x) x x
Substituting the excess (E) concentration to the Ka equation:
[tex]K_{a} = \frac{[x ][x]}{1.0 \ x \ 10^{-4} - x }[/tex]
Simplifying the equation would yield a quadratic equation:
[tex] x^{2} + K_{a}x-(1.0 \ x \ 10^{-4}) K_{a}=0 [/tex]
The Ka for HClO is an experimental data which was determined to be 2.9 x 10^-8. Substitute this to the equation, determine the roots, then you get the value for x, which is the concentration of H3O+ and ClO-. Just use your calculator feature Shift-Solve.
x = 1.688 x 10^-6 M = [H3O+] = [ClO-]
Then, you can determine the conc of [OH-] through pH.
pH = -log {H3O+] = -log [1.688 x 10^-6] = 5.77
pOH = 14 - pH = 14 - 5.77 = 8.23
pOH = 8.23 = -log [OH-]
[OH-] = 5.89 x 10^-9 M
Also, since HClO is (1.0x10^-4 - x), then it's concentration would be:
[HClO] = 1.0x10^-4 - 1.688 x 10^-6 = 9.83 x10^-5 M
Let's summarize all concentrations:
[HClO] = 9.83 x10^-5 M
[OH-] = 5.89 x 10^-9 M
[H3O+] = [ClO-] = 1.688 x 10^-6 M
Since the solution is dilute, H2O is relatively higher in concentration.
Thus in relative amounts, the order would be
H2O >>> HClO > H3O+ = ClO- > OH-
The Formula is:
Molar Mass of an Element = x Relative mass of atoms Molar mass constant (1g / mol)
Further Explanation
Understand molar mass
Molar mass = mass (in grams) of 1-mol substances
Molar mass is the mass (in grams) of one mole of a substance. By using the atomic mass of an element and multiplying it by the conversion factor of grams per mole (g / mol), you can calculate the molar mass of the element.
Look for the relative atomic mass of elements
Relative atomic mass:
Hydrogen = 1,007
Carbon = 12.0107
Oxygen = 15,9994
Chlorine = 35,453
The relative atomic mass of an element is the average mass of a sample of all its isotopes in atomic units. This information can be found in the periodic table of elements.
Multiply the atomic mass relative to the molar mass constant
Molar Mass of an Element = x Relative mass of atoms Molar mass constant (1g / mol)
Hydrogen = 1,007 x 1g / mol = 1,007 g / mol
Carbon = 12.0107 g / mol
Oxygen = 15,999 g / mol
Chlorine = 35,453 g / mol
H2: 1,007 x 2 = 2,014 g / mol
O2: 15,999 x 2 = 31,9988 g / mol
C2: 35,453 x 2 = 70,096 g / mol
example:
Hydrochloric acid
HCl -> 1 hydrogen atom, 1 chlorine atom
Glucose
C6H12O6 -> 6 carbon atoms, 12 hydrogen atoms, 6 oxygen atoms
Learn More
Molar mass https://brainly.com/question/2194946
Calculate molar mass https://brainly.com/question/11444952
Details
Class: Middle/High School
Subject: Chemistry
Keywords: Mass, Molar, atoms