Question

2. Рассчитать массу гидроксида калия, если молярная концентрация раствора равна 0, 3 моль/л, а объём раствора 500 мл.

Answer 1

m(KOH) = m(р-ра) * n(KOH) = 500мл * 0.15 моль = 75г

Answer 2

Calculating the Mass of Potassium Hydroxide

To calculate the mass of potassium hydroxide, we can use the formula:

Mass = Molar concentration × Volume × Molar mass

Given: - Molar concentration of the solution = 0.3 mol/L - Volume of the solution = 500 mL - Molar mass of potassium hydroxide (KOH) = 56.11 g/mol

Calculation

First, we need to convert the volume from milliliters to liters: - Volume = 500 mL = 500/1000 L = 0.5 L

Now, we can calculate the mass of potassium hydroxide: - Mass = Molar concentration × Volume × Molar mass - Mass = 0.3 mol/L × 0.5 L × 56.11 g/mol - Mass = 8.4165 g

So, the mass of potassium hydroxide in the solution is approximately 8.42 grams.