Question

В растворе массой 200г содержится нитритная кислота, массовая доля которой - 2,35%. Определите колличество ионов H+ в этом растворе, если степень диссоциации кислоты - 2%

Answer 1

Масса кислоты- 200*0,0235= 4,7 г
Количество вещества кислоты- 4,7/63= 0,075 моль (моль- молярная масса)
Количество ионов- 0,075*0,02= 0,0015 моль

Answer 2

Calculation of the Number of H+ Ions in the Solution

To determine the number of H+ ions in the solution, we need to consider the concentration of nitric acid (HNO2) and its degree of dissociation.

Given: - Mass of the solution = 200 g - Mass fraction of nitric acid (HNO2) = 2.35% - Degree of dissociation of nitric acid (HNO2) = 2%

To calculate the number of H+ ions, we need to follow these steps:

1. Calculate the mass of nitric acid (HNO2) in the solution: - Mass of HNO2 = Mass of the solution * Mass fraction of HNO2 - Mass of HNO2 = 200 g * (2.35/100) = 4.7 g

2. Calculate the molar mass of nitric acid (HNO2): - Molar mass of HNO2 = 1 * (1.00784 g/mol) + 14.00674 g/mol + 16.00 g/mol - Molar mass of HNO2 = 63.01874 g/mol

3. Calculate the number of moles of nitric acid (HNO2): - Number of moles of HNO2 = Mass of HNO2 / Molar mass of HNO2 - Number of moles of HNO2 = 4.7 g / 63.01874 g/mol ≈ 0.0745 mol

4. Calculate the number of moles of H+ ions: - Number of moles of H+ ions = Number of moles of HNO2 * Degree of dissociation - Number of moles of H+ ions = 0.0745 mol * (2/100) = 0.00149 mol

5. Calculate the number of H+ ions: - Avogadro's number (NA) = 6.02214076 × 10^23 mol^-1 - Number of H+ ions = Number of moles of H+ ions * NA - Number of H+ ions = 0.00149 mol * 6.02214076 × 10^23 mol^-1 ≈ 8.96 × 10^20 ions

Therefore, the number of H+ ions in the solution is approximately 8.96 × 10^20 ions.