In the titration of 238.0 mL of a 5.60×10-2 M solution of acid H3A (Ka1 = 1.0×10-3, Ka2 = 5.0×10-8, Ka3 = 2.0×10-12), calculate the volume of 2.90 M NaOH required to reach the following pH values. pH = 9.50 Volume required = mL pH = 4.70 Volume required = mL

When pH = 9.50 ; Volume = 14.8 L

When pH = 4.70 ; Volume = 4.51 L

Explanation:

We all know that:

So let us first calculate the pKa values of the following Ka:

Given that:

Ka1 = 1.0×10⁻³

Ka2 = 5.0×10⁻⁸

Ka3 = 2.0×10⁻¹²

For ; we have

=

= 3.00

=

= 7.30

=

= 11.70

At pH = 4.70:

The pH (4.70) is closer to than and .

However, the only important pKa for the dissociation of the acid will be directed towards only  

So: At pH = 4.70

-log = pH = 4.70

              ⇄            

where;

so, we have:

Given that;

283.0 mL of solution is given:

Then ; 283.0 mL = 0.283 L

However;

=

= 0.013328

=

= 0.01307 mole

moles of NaOH required to convert to  i.e

=

Finally; the volume of NaOH required =

= 0.004507

= 4.51 mL

When pH = 4.70 ; Volume = 4.51 L

When pH = 9.50

We try to understand that the average of and yields 9.50

i.e

=  

= 9.50

Here; virtually all,  is in  form;

SO; the moles of NaOH required to convert to will be:

= 2 × initial   = volume of NaOH × 1.8 M

= 2 × 1.3328 × 10⁻² mol = Volume  of NaOH × 1.8 M

Volume  of NaOH  =

= 0.1481 L

= 14.8 L

When pH = 9.50 ; Volume = 14.8 L

c)red bank

explanation:

red bank is a borough in monmouth county, new jersey, incorporated in 1908 and located on the navesink river, the area's original transportation route to the ocean and other ports.

answer: cellular respiration takes in food and uses it to create atp, a chemical which the cell uses for energy. usually, this process uses oxygen, and is called aerobic respiration. it has four stages known as glycolysis, link reaction, the krebs cycle, and the electron transport chain.