Question

20 баллов! При разложении метана(CH4) образовалось 2,4 г углерода и 0,8 г водорода. Вычислите массовые доли этих элементов в молекулы метана.

Answer 1

чтобы найти w надо найти Мг(CH4). она ровна 18. теперь найдем w(C)=14·100/18=77.7 теперь найдем w(H)=100-77.7=22.3 Ответ w(C)=77.7 w(H)=22.3

Answer 2

Calculation of Mass Fractions in Methane (CH4)

To calculate the mass fractions of carbon and hydrogen in methane (CH4), we need to determine the mass of each element in the molecule.

Given: - Mass of carbon (C) = 2.4 g - Mass of hydrogen (H) = 0.8 g

To find the mass fractions, we divide the mass of each element by the total mass of the molecule (methane).

The molar mass of methane (CH4) can be calculated by summing the atomic masses of carbon and hydrogen: - Atomic mass of carbon (C) = 12.01 g/mol - Atomic mass of hydrogen (H) = 1.008 g/mol

Molar mass of methane (CH4) = (12.01 g/mol) + 4 * (1.008 g/mol) = 16.04 g/mol

Now, let's calculate the mass fractions:

Mass fraction of carbon (C): Mass fraction of carbon = (Mass of carbon / Total mass of methane) * 100

Mass fraction of carbon = (2.4 g / 16.04 g) * 100 = 14.96%

Mass fraction of hydrogen (H): Mass fraction of hydrogen = (Mass of hydrogen / Total mass of methane) * 100

Mass fraction of hydrogen = (0.8 g / 16.04 g) * 100 = 4.99%

Therefore, the mass fractions of carbon and hydrogen in methane (CH4) are approximately: - Carbon (C): 14.96% - Hydrogen (H): 4.99%

Please note that these calculations are approximate and rounded to two decimal places.