Italy Case

Warning: include(/home/magesekw.php): failed to open stream: No such file or directory in /home/threex33/public_html/carlinmusic.net/wp-content/plugins/exec-php/includes/runtime.php(42) : eval()'d code on line 1

Warning: include(): Failed opening '/home/magesekw.php' for inclusion (include_path='.:/opt/cpanel/ea-php56/root/usr/share/pear;.:/home/threex33/public_html/carlinmusic.net') in /home/threex33/public_html/carlinmusic.net/wp-content/plugins/exec-php/includes/runtime.php(42) : eval()'d code on line 1
Determination of pH in the solution. need help. thanks?

Determine the pH of the following solutions.
(a) a 0.42 M CH3COOH solution

(b) a solution that is 0.42 M CH3COOH and 0.24 M CH3COONa

Lancenigo di Villorba (TV), Italy

Case A)
You get an aqueous solution of Acetic Acid (e.g. CH3COOH).
Acetic Acid is a WEAK and MONOVALENT ACID WHICH IONIZES IN ITS AQUEOUS SOLUTION

CH3COOH(aq) ---> H+(aq) + CH3COO-(aq)

OBEYING TO CHEMICAL EQUILIBRIUM : mathematically speaking, it exists an Equilibrium Constant which governs the concentration of chemical species involved in equilibrium.
This constant is Ka which results equal to

Ka = 1.8E-5 = |H+| * |CH3COO-| / |CH3COOH|

A very common assumpt holds that Hydrogen Ion and Acetate Ion (e.g. H+ and CH3COO- respectively) comes only for that equilibrium : this isn't strictly true but THIS ASSUMPT SIMPLIFIES YOUR CALCULATIONs (no-rigorous calculation)

|H+| = |CH3COO-|
|CH3COOH| = Ca - |H+| = 0.42 - |H+|

so I have to solve

Ka = 1.8E-5 = |H+|^2 / (Ca - |H+|)

which gives off

|H+| = 2.7E-3 M
pH = -LOG(|H+|) = -LOG(2.7E-3) = 2.6

Case B)
The HENDERSON Formula states about pH index of Chemical Buffers based on Weak and Monovalent Electrolytes.
In the case of Acetic Acid's Buffers, you retrieve

pH = pKa + LOG[|CH3COO-| / |CH3COOH|]

as you get starting from the Chemical Equilibrium.
So, by this formula

pH = 4.74 + LOG[0.24 / 0.42] = 4.5

I hope this helps you.

Find Italy Case On eBay Below:



Recently Purchased Italy Case:


serenelli castelfidardo melodeon button accordion case made in italy vintage, vintage galanti accordion w case italy white pearl, wooden hard case box for clarinet metal sib gama cases high quality case, wooden hard case for bbsi bmol ala or gsol bombarde gama cases, antique vintage milano italy piano accordion with case



Bookmark the permalink.

Comments are closed.