Question

В химических лабораториях для первой помощи при попадании кислот на кожу,слизистые оболочки глаз,рта применяют 2% раствор гидрокарбоната натрия NaHCO3.Считая плотность раствора равной 1г/см кубический,вычислите,какой юбъём 2%-ого раствора можно приготовить из питьевой воды массой 200г

Answer 1

x - масса растворенного NaHCO3.

m(p-pa) = m(NaHCO3)/W(NaHCO3)

m(p-pa) = m(NaHCO3) + m(H2O)

Подставляем известные значени, получаем уравнения, решаем уравнение:

х + 200 = х/0,02

0,02х + 4 = х

4 = 0,98х

х = 4/0,98

х = 4,08 г

m(p-pa) = 200 + 4,08 = 204,08 г

V(p-pa) = m(p-pa)*po = 204*1 = 204 мл.

Answer 2

Calculating the Volume of 2% Sodium Bicarbonate Solution

To calculate the volume of a 2% sodium bicarbonate (NaHCO3) solution that can be prepared from 200g of water, we can use the formula:

% concentration = (mass of solute / volume of solution) x 100

Given: - Mass of water = 200g - % concentration of the solution = 2% - Density of the solution = 1g/cm^3

We can calculate the volume of the 2% solution using the given mass of water.

Calculation

First, we need to find the mass of sodium bicarbonate (NaHCO3) required to make the 2% solution. We can use the formula:

% concentration = (mass of solute / volume of solution) x 100

Rearranging the formula to solve for the mass of solute: mass of solute = (% concentration x volume of solution) / 100

Given: - % concentration = 2% - Volume of solution = ? - Mass of solute = ?

Using the given density of the solution (1g/cm^3), we can calculate the volume of the solution.

Let's calculate the mass of sodium bicarbonate required and the volume of the 2% solution that can be prepared from 200g of water.

Solution

The mass of sodium bicarbonate (NaHCO3) required: mass of solute = (2% x 200g) / 100 = 4g

The volume of the 2% sodium bicarbonate solution that can be prepared from 200g of water: volume of solution = mass of water + mass of solute = 200g + 4g = 204g

As the density of the solution is 1g/cm^3, the volume of the 2% solution is: volume of solution = 204cm^3

Therefore, from 200g of water, a volume of 204cm^3 of 2% sodium bicarbonate solution can be prepared.

Conclusion

From 200g of water, it is possible to prepare a volume of 204cm^3 of a 2% sodium bicarbonate solution.