Question

При нагріванні 68 г суміші карбонату та гідрокабонату натрію виділилось 0,22 моль газу. Визначіть масові частки кожної солі у суміші.

Answer 1

m(Na2CO3 + NaHCO3) = 68г

 

n(газ)=0,22 моль 

_______________________

w(Na2CO3)-?

w(NaHCO3)-? 

 

          х -?                        0.22 моль 

1)   2NaHCO3 = Na2CO3 + СО2 + Н2O

        2 моль                      1 моль 

    

 

        n(NaHCO3)=0.44 моль 

        m(NaHCO3)=0.44 * (23+1+12+48)= 36.96
                             

        w(NaHCO3)= 36.96/68 * 100%= 54,4%

 

2)w(Na2CO3)=100% - 54,4%= 45,6% 

 

 

 

Відповідь: w(Na2CO3)=45,6% 

                  w(NaHCO3)=54,4%

 

 

Answer 2

Calculating the Mass Fractions of Sodium Carbonate and Sodium Bicarbonate

To determine the mass fractions of sodium carbonate (Na2CO3) and sodium bicarbonate (NaHCO3) in the mixture, we can use the concept of stoichiometry and the amount of gas released during the heating process.

Given: - Mass of the mixture = 68 g - Gas released = 0.22 moles

First, we need to find the molar masses of sodium carbonate and sodium bicarbonate.

The molar mass of Na2CO3: - Sodium (Na) = 22.99 g/mol - Carbon (C) = 12.01 g/mol - Oxygen (O) = 16.00 g/mol Molar mass of Na2CO3 = 22.99*2 + 12.01 + 16.00*3 = 105.99 g/mol

The molar mass of NaHCO3: - Sodium (Na) = 22.99 g/mol - Hydrogen (H) = 1.01 g/mol - Carbon (C) = 12.01 g/mol - Oxygen (O) = 16.00 g/mol Molar mass of NaHCO3 = 22.99 + 1.01 + 12.01 + 16.00*3 = 84.01 g/mol

Now, we can calculate the moles of each compound present in the mixture using the given gas release.

Moles of gas released = 0.22 moles Moles of Na2CO3 = x Moles of NaHCO3 = 0.22 - x

Using the molar masses and moles, we can calculate the mass of each compound in the mixture.

The mass of Na2CO3 = (moles of Na2CO3) * (molar mass of Na2CO3) The mass of NaHCO3 = (moles of NaHCO3) * (molar mass of NaHCO3)

Finally, we can calculate the mass fractions of each compound in the mixture.

Mass fraction of Na2CO3 = (mass of Na2CO3) / (total mass of the mixture) * 100% Mass fraction of NaHCO3 = (mass of NaHCO3) / (total mass of the mixture) * 100%

Let's calculate these values.