The pH of a solution is 3.3. What is its hydrogen ion concentration? Hydrogen ion concentration \( \left[\mathrm{H}^{+}\right] \approx \square \) moles per liter. (Use scientific notation. Use the multiplication symbol in the math palette as needed. Round to the nearest tenth as needed.)

To find the hydrogen ion concentration \(\left[\mathrm{H}^{+}\right]\) from the pH, you can use the formula \(\left[\mathrm{H}^{+}\right] = 10^{-\text{pH}}\). Given that the pH is 3.3, you would calculate \(\left[\mathrm{H}^{+}\right] = 10^{-3.3}\). This results in \(\left[\mathrm{H}^{+}\right] \approx 5.0 \times 10^{-4}\) moles per liter. Now, pH doesn’t just reflect acidity; it also plays a critical role in biological and chemical systems. Many enzymes, for instance, require specific pH levels to function optimally—like pepsin, which operates best in the acidic environment of the stomach! If you're working with pH and H⁺ concentrations, remember that small changes in pH represent big changes in acidity. A pH decrease of just 1 (like from 3.3 to 2.3) means there’s ten times more H⁺ ions! Watch out for assumptions that pH changes linearly with acidity; it’s all about that logarithmic scale!