Question

Определите молекулярную формулу алкана, массовая доля углерода в котором 81.82

Answer 1

CxHy

w(H)=100%-81,82%= 18,18%

x:y=w(C)/12:w(H)/1= 81,82/12:18,18/1=6,8:18,18=1:3(грубо если взять)

У меня получилось CH3,хотя должно было получится CH4 я так понимаю.Возможно у вас там опечатка. 

Answer 2

Molecular Formula and Carbon Mass Percentage

The molecular formula of an alkane with a mass fraction of carbon equal to 81.82% can be determined using the following steps:

1. Calculate the mass fraction of hydrogen in the alkane. 2. Determine the ratio of carbon to hydrogen in the alkane. 3. Use the ratio to derive the molecular formula.

Let's proceed with these steps.

1. Calculate the mass fraction of hydrogen in the alkane: - The mass fraction of carbon is given as 81.82%. - Since the alkane is composed of only carbon and hydrogen, the total mass fraction of both elements is 100%.

2. Determine the ratio of carbon to hydrogen in the alkane: - Subtracting the mass fraction of carbon from 100% gives the mass fraction of hydrogen, which is 100% - 81.82% = 18.18%.

3. Use the ratio to derive the molecular formula: - The ratio of carbon to hydrogen in the alkane can be calculated using the given mass fractions.

Based on the calculated ratio, the molecular formula of the alkane can be determined.