Use the table to answer the following question. The table shows the pH of four body fluids and the resulting color when each is tested with red and blue litmus paper.
Body fluid
pH
Red Litmus
Blue Litmus
Blood
7.4
turns blue
no change
Bile
8.2
turns blue
no change
Saliva
6.8
no change
turns red
Gastric juice
1.7
no change
turns red
According to the data what kind of substance is gastric juice?
O A. it is a strong base since the blue litmus paper turns red and the pH is 1.7
o B. it is a weak acid since the blue litmus paper turns red and the pH is 1.7
O
C it is a weak base since the blue litmus paper turns red and the pH is 1.7
O D. it is a strong acid since the blue litmus paper turns red and the pH is 1.7

Explanation:

From the given information ;the objective is to determine how the instructor made the 0.25L elution buffer

0.25 L elution buffer = 250 mL elution butter

The breaking buffer that we use this week contains

10mM Tris    =   0.01 M

150mM NaCl  =   0.15 M

300mM imidazole.  = 0.3 M

The stock concentration  of Tris in 1M

Therefore ; by using the formula: ; we can determine the volume in the preparation; so;

In NaCl, The amount of stock concentration is 5 M

so; using the same formula; we have:

From Imidazole ; the amount of stock concentration is

Thus; we can have a table as shown as :

Stock concentration        volume to be added        Final concentration

1 M of Tris                              2.5 mL                            10 mM

5 M of  NaCl                          7.5 mL                             150 mM

1 M of Imidazole                    75  mL                            300  mM

In conclusion. the addition of all the volume make up the 250 mL elution buffer that is equivalent to 0.25 L.