Question

К раствор объёмом 140 мл с массовой долей NaOH 24% и плотностью 1.27 г/мл при лили раствор HCl объёмом 120 мл с массовой долей 20% и плотностью 1,16 г/мл. Определите массу образовавшейся соли

Answer 1

Решение есть на фотографии

Answer 2

Calculation of the Mass of the Formed Salt

To determine the mass of the formed salt, we need to calculate the number of moles of NaOH and HCl in the given volumes and concentrations. Then, we can use the balanced chemical equation to determine the stoichiometry of the reaction and calculate the mass of the formed salt.

Given information: - Volume of NaOH solution: 140 mL - Mass fraction of NaOH: 24% - Density of NaOH solution: 1.27 g/mL - Volume of HCl solution: 120 mL - Mass fraction of HCl: 20% - Density of HCl solution: 1.16 g/mL

First, let's calculate the mass of NaOH in the given volume of solution: Mass of NaOH = Volume of NaOH solution * Density of NaOH solution * Mass fraction of NaOH.

Substituting the given values: Mass of NaOH = 140 mL * 1.27 g/mL * 0.24 = 43.008 g

Next, let's calculate the mass of HCl in the given volume of solution: Mass of HCl = Volume of HCl solution * Density of HCl solution * Mass fraction of HCl.

Substituting the given values: Mass of HCl = 120 mL * 1.16 g/mL * 0.20 = 27.936 g

Now, let's calculate the number of moles of NaOH and HCl using their molar masses: Number of moles = Mass / Molar mass.

The molar mass of NaOH is 22.99 g/mol for Na, 16.00 g/mol for O, and 1.01 g/mol for H, giving a total molar mass of 39.99 g/mol. The molar mass of HCl is 1.01 g/mol for H and 35.45 g/mol for Cl, giving a total molar mass of 36.46 g/mol.

Number of moles of NaOH = 43.008 g / 39.99 g/mol = 1.076 mol Number of moles of HCl = 27.936 g / 36.46 g/mol = 0.766 mol

From the balanced chemical equation for the reaction between NaOH and HCl, we know that 1 mole of NaOH reacts with 1 mole of HCl to form 1 mole of salt.

Therefore, the number of moles of the formed salt is equal to the number of moles of NaOH or HCl, whichever is smaller. In this case, the number of moles of HCl is smaller, so the number of moles of the formed salt is 0.766 mol.

Finally, let's calculate the mass of the formed salt using its molar mass: Mass of the formed salt = Number of moles of the formed salt * Molar mass of the salt.

Unfortunately, the specific salt formed in the reaction is not provided in the question. Therefore, we cannot determine the exact molar mass of the salt and calculate its mass.

Please provide the specific salt involved in the reaction so that we can calculate the mass of the formed salt accurately.