Question

Определите молярную массу двухосновной кислоты , если при полной нейтрализации 9.8г ее израсходованно 8г гидроксида натрия

Answer 1

Уравнение реакции:
H2An + 2NaOH = Na2An + 2H2O
m(H2An) / [n(H2An) * M(H2An)] = m(NaOH) / [n(NaOH) * M(NaOH)]
M(H2An) = 9,8 * 2 * 40 / [8 * 1] = 98 г/моль

Ответ: 98 г/моль

Answer 2

Molar Mass of a Dibasic Acid

To determine the molar mass of a dibasic acid, we can use the given information about the complete neutralization of the acid with sodium hydroxide.

Given: - Mass of the dibasic acid = 9.8g - Mass of sodium hydroxide used for neutralization = 8g

The reaction between the dibasic acid and sodium hydroxide can be represented as follows: ``` H2A + 2NaOH → Na2A + 2H2O ``` Where H2A represents the dibasic acid and Na2A represents the sodium salt of the dibasic acid.

From the reaction, we can see that 1 mole of dibasic acid reacts with 2 moles of sodium hydroxide.

Calculation

1. Calculate the moles of sodium hydroxide used: - Moles of NaOH = Mass of NaOH / Molar mass of NaOH - Moles of NaOH = 8g / 40g/mol (molar mass of NaOH) - Moles of NaOH = 0.2 moles

2. Since 1 mole of dibasic acid reacts with 2 moles of sodium hydroxide, the moles of dibasic acid used in the reaction will be half of the moles of sodium hydroxide used: - Moles of dibasic acid = 0.2 moles / 2 - Moles of dibasic acid = 0.1 moles

3. Calculate the molar mass of the dibasic acid: - Molar mass = Mass of dibasic acid / Moles of dibasic acid - Molar mass = 9.8g / 0.1 moles - Molar mass = 98 g/mol

Conclusion

The molar mass of the dibasic acid is 98 g/mol based on the given information about the complete neutralization of the acid with sodium hydroxide.