3. Using Equation 18-5 and the pKIn value you found, determine the ratio [In-]/[HIn] at the pH in the middle of the range you studied (i. e., pH = 6.0 for bromocresol purple, pH = 7.0 for bromothymol blue, and pH = 7.7 for phenol red). Show how you accomplished this. Draw a conclusion about the relative concentrations of In- and HIn at pH values very close to the pKIn of the indicator.

Explanation:

[In-]/ [HIn] = [KIn]/ [H3O+]

Use the  values of  PkIN = 7.1,

KIN=8.14E-8, and

[H3O+] = 10E-7

To plug them in as follows:

(8.14E-8)/ (10E-7) = 0814, thus shows a  very close  ratio 1 to 1

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).