Respuesta :
- The correct answer that will decrease the PH is ( HNO3)
- Since the unknown solution is containing a pH of 7.2, it means it is more basic not acidic, then to make it have decrease in PH, then acidic substance needs to be added to it so as to reduce the PH from 7.2
- KOH : potassium hydroxide is a base, if it is added to the substance, it will increase in PH value
- NH3 : Ammonia is a base, if it is added to the substance, it will increase in PH value
- HNO3 : Trioxonitrate (v) acid is an acid , adding it to the substance will make the PH to be acidic hence decrease in PH
- When a substance is neither acidic nor basic it can be regarded as neutral.
- The pH scale gives the measurements of how acidic or basic a particular substance is.
- The pH scale can be given in the ranges starting from 0 to 14.
- A pH of 7 is considered neutral.
Therefore, decrease in PH can be achieved by adding acidic substance.
Learn more at : https://brainly.com/question/11936640?referrer=searchResults