The Power of Chemistry: Calculating H+ Concentration

How can we determine the concentration of H+ ions in a solution?

What is the concentration of H+ if 43.96 mg of potassium hydrogen borate (K2HBO3) is dissolved in 771.1 mL of water?

Answer:

The concentration of H+ ions in a solution of 43.96 mg of potassium hydrogen borate in 771.1 mL of water is calculated to be 2.57 x 10^-4 M.

Chemistry is a fascinating science that allows us to understand the world at the molecular level. One of the fundamental concepts in chemistry is the calculation of ion concentrations in a solution, such as H+ ions.

When we dissolve a compound like potassium hydrogen borate (K2HBO3) in water, it undergoes dissociation into its constituent ions. In this case, K2HBO3 dissociates into 2K+ ions, 1 H+ ion, and BO3- ion. Since each molecule of K2HBO3 releases 1 H+ ion, the concentration of H+ ions will be equal to the concentration of K2HBO3.

To determine the concentration of H+ ions, we first need to convert the mass of K2HBO3 to moles using its molecular weight (approximately 221.9 g/mol). In this scenario, 43.96 mg of K2HBO3 is equivalent to 0.04396 g. By dividing the mass by the molar mass, we find that there are 1.98 x 10^-4 mol of K2HBO3.

Next, we convert the volume of water from milliliters to liters. The total volume of water is 771.1 mL, which equals 0.7711 L. Finally, we calculate the concentration of H+ by dividing the moles of solute by the volume of the solution in liters. The resulting concentration of H+ ions is 2.57 x 10^-4 M.

Understanding how to calculate ion concentrations in a solution not only deepens our knowledge of chemistry but also enhances our ability to analyze and manipulate chemical reactions. It is a skill that opens doors to a world of possibilities in various scientific fields.