What is the pH of 0.0000043M HNO3 ? (3 sig figs, round the last digit only if needed)

pH = 5.37

Explanation:

We'll begin by obtaining the concentration of the hydrogen ion in the solution. This can be obtained as follow:

HNO₃ (aq) —> H⁺ (aq) + NO₃¯ (aq)

From the balanced equation above,

1 mole of HNO₃ produced 1 mole of H⁺.

Therefore, 4.3×10¯⁶ M HNO₃ will also produce 4.3×10¯⁶ M H⁺.

Finally, we shall determine the pH of the solution. This can be obtained as follow:

Concentration of Hydrogen ion [H⁺] = 4.3×10¯⁶ M

pH =?

pH = –Log [H⁺]

pH = –Log 4.3×10¯⁶

pH = 5.37

Therefore, the pH of the solution is 5.37

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