Determine the concentration of a solution of sodium hydroxide (NaOH) using a 0.500M Potassium Hydrogen Phthalate (KHP) standard solution. Acid-base indicator phenolphthalein is added in its (colorless) acidic form to a precise volume sample of KHP. The base NaOH is slowly added to the same of KHP. Once all the KHP has reacted with the base, the first excess drop of NaOH will cause the indicator to convert to its basic (pink) form.

The answer is letter c

You would be correct, boiling water does disinfect contamination.    the property of disinfecting means to kill  germs, bacteria and other pathogens or contamination  that might cause an infection or cause a person to become sickly. a couple methods of disinfecting are using soap, other cleaning supplies or by simply "boiling" the contaminate.  the reason why boiling water disinfects certain attributes is because some cells cannot survive the heat and pressure.

Answer:   d.  carbon dioxide.

The ratio is 3: 2. i.e. c.