Question

Пробу воздуха объёмом 112 л пропустили через раствор гидроксида кальция. В результате выпал осадок соли массой 0.4 г. Определите содержание углекислого газа во взятой пробе воздуха. Соответствует ли содержание углекислого газа допустимой в норме?

Answer 1

Ca(OH)2+CO2=CaCO3+H2O

               1         1

кол-во в-ва осадка СаСО3=0,4:100=0,004моль; объем СО2=0,004Х22,4=0,0896л

объемная доля СО2 в воздухе=(0,0896:112)Х100%=0,08%

Answer 2

Calculation of Carbon Dioxide Content in the Air Sample

To determine the content of carbon dioxide (CO2) in the air sample, we can use the information provided about the mass of the precipitated salt and the volume of the air sample.

Given: - Volume of air sample: 112 L - Mass of precipitated salt: 0.4 g

To calculate the content of CO2, we need to find the number of moles of the precipitated salt. We can then use the stoichiometry of the reaction to determine the number of moles of CO2 produced.

The balanced chemical equation for the reaction between calcium hydroxide (Ca(OH)2) and carbon dioxide (CO2) is:

Ca(OH)2 + CO2 → CaCO3 + H2O

From the equation, we can see that 1 mole of Ca(OH)2 reacts with 1 mole of CO2 to produce 1 mole of CaCO3.

To find the number of moles of CaCO3, we can use the molar mass of CaCO3, which is approximately 100.09 g/mol.

Using the given mass of the precipitated salt (0.4 g), we can calculate the number of moles of CaCO3:

Number of moles of CaCO3 = Mass of CaCO3 / Molar mass of CaCO3

Number of moles of CaCO3 = 0.4 g / 100.09 g/mol

Now, since 1 mole of CaCO3 is produced from 1 mole of CO2, the number of moles of CO2 is also equal to the number of moles of CaCO3.

Therefore, the content of CO2 in the air sample can be calculated as follows:

Content of CO2 = Number of moles of CO2 / Volume of air sample

Content of CO2 = Number of moles of CaCO3 / Volume of air sample

Let's calculate the content of CO2 using the given values:

Number of moles of CaCO3 = 0.4 g / 100.09 g/mol = 0.003998 mol

Content of CO2 = 0.003998 mol / 112 L = 0.0000357 mol/L

Conclusion

The content of carbon dioxide (CO2) in the air sample is approximately 0.0000357 mol/L.

To determine if this content is within the permissible range, we would need to compare it to the relevant standards or regulations for CO2 levels in the air. Unfortunately, the search results did not provide specific information about the permissible range for CO2 content in the air. Therefore, without additional information, we cannot determine if the CO2 content in the air sample is within the permissible range.