Respuesta :
An unknown solution has a pH of 6.8. The chemical that will increase the pH is NaOH. The correct option is a.
What are acid and bases?
Acids have lower pH, and they are sour and bases have high pH, and they are bitter in taste.
HCl, NH3, HNO3 are all acids and acid decrease the pH. Only NaOH is a base, and it will increase the pH.
Thus, the correct option is a. NaOH.
Learn more about acid and bases
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