Question

Помогите, пожалуйста =)1. Сколько воды необходимо прилить к 600 мл 4,61М раствора хлорида натрия; плотность которого 1,172 г/мл, чтобы приготовить 2,84М раствор, плотность которого 1,109 г/мл? Выразите данные концентрации исходного и полученного растворов в процентах.2. При выпаривание 2 л раствора было получено 16,4 г нитрата кальция. Определите молярную концентрацию взятого раствора.

Answer 1

Первая задачка хорошаа)

Answer 2

Calculating the Amount of Water Needed to Prepare a 2.84M Sodium Chloride Solution

To calculate the amount of water needed to prepare a 2.84M sodium chloride solution from a 4.61M solution, we can use the formula:

M1V1 = M2V2

Where: - M1 = initial molarity - V1 = initial volume - M2 = final molarity - V2 = final volume

Given: - M1 = 4.61M - V1 = 600 ml - M2 = 2.84M - Density of initial solution = 1.172 g/ml - Density of final solution = 1.109 g/ml

We can calculate the initial and final volumes using the formula and then find the amount of water needed.

Let's calculate the initial and final volumes first.

The initial volume (V1) can be calculated using the formula: V1 = M2V2 / M1

The final volume (V2) can be calculated using the formula: V2 = V1 + amount of water

Now, let's calculate the initial and final volumes.

Initial Volume (V1): V1 = (2.84M * 600ml) / 4.61M V1 ≈ 367.87 ml

Final Volume (V2): V2 = 367.87 ml + amount of water

To find the amount of water needed, we can subtract the initial volume from the final volume: amount of water = V2 - V1

Next, we'll calculate the amount of water needed and express the concentrations of the initial and final solutions in percentages.

Expressing Concentrations in Percentages

The concentrations of the initial and final solutions can be expressed in percentages using the formula: Concentration (%) = (mass of solute / volume of solution) * 100

We'll use this formula to express the concentrations of the initial and final solutions in percentages.

Let's proceed with the calculations.