What is the pH of a solution obtained by mixing 3.15 g HNO3 and 2.6 g NaBr in water to create 755 L of solution

pH = 4.179

Explanation:

∴ mass HNO3 = 3.15 g

∴ mass NaBr = 2.6 g

∴ Vsln = 755 L

∴ molar mass HNO3 = 63.01 g/mol

⇒ moles HNO3 = (3.15 g)*(mol/63.01 g) = 0.05 mol

⇒ [HNO3] = (0.05 mol)/(755 L) = 6.62 E-5 M

HNO3 is a strong acid:

∴ [HNO3] = [H3O+]

⇒ [H3O+]= 6.62 E-5 M

∴ pH = - Log [H3O+]

pH = - Log (6.62 E-5)

⇒ pH = 4.179