Question

К 250 мл воды добавили 5г хлорида натрия. Определите массовую долю соли в полученном растворе. (Ответ округлите до целого числа) ДАЮ 20 БАЛОВ ПЖ СРОЧНО НАДО​

Answer 1

Объяснение:

w(NaCl) = m(NaCl) /(m(H2O) +m(NaCl)) = m(NaCl) /(V(H2O) *p(H2O) +m(NaCl) = 5/(250*1+5) = 0.02;

Ответ: 2%

Answer 2

Calculation of Mass Fraction of Salt in the Solution

To determine the mass fraction of salt in the solution, we need to calculate the mass of the salt and the total mass of the solution.

Given: - Volume of water = 250 ml - Mass of sodium chloride (salt) = 5 g

To calculate the mass fraction of salt, we can use the formula:

Mass Fraction of Salt = (Mass of Salt / Total Mass of Solution) * 100

First, let's convert the volume of water from milliliters to grams. Since the density of water is approximately 1 g/ml, the mass of water will be equal to its volume:

Mass of Water = Volume of Water = 250 g

Next, we can calculate the total mass of the solution by adding the mass of water and the mass of salt:

Total Mass of Solution = Mass of Water + Mass of Salt

Substituting the given values:

Total Mass of Solution = 250 g + 5 g = 255 g

Now, we can calculate the mass fraction of salt:

Mass Fraction of Salt = (5 g / 255 g) * 100

Calculating this expression:

Mass Fraction of Salt = (0.0196) * 100 ≈ 1.96%

Therefore, the mass fraction of salt in the obtained solution is approximately 1.96%.

Please note that the answer has been rounded to the nearest whole number, as requested.