Question

При сжигании углеводорода получили 35,2г оксида углерода (IV) и 14,4г воды. Относительная плотность алкена по воздуху 1,93.Найдите молекулярную формулу алкена.

Answer 1

СхНу+О2=СО2 +Н2О

колчество (С)=м(СО2)/М(СО2)=35,2/44=0,8моль

кол-во(Н)= 2*м(Н2О)/М(Н2О)=1,6 моль

n(C):n(H)=х:у=0,8:1,6=4:8

т.к формула алкена равна СпН2п, то М(СпН2п)=14п

далее находим М(СпН2п) через плотность по воздуху,

М=Д(в)*29= 55,97. затем приравниваем молярные массы ,получается,

14п=56

п=4 

Ответ:С4Н8

Answer 2

Calculation of the Molecular Formula of the Alkene

To find the molecular formula of the alkene, we need to analyze the given information about the combustion of the hydrocarbon.

According to the information provided, when the hydrocarbon is burned, 35.2g of carbon dioxide (CO2) and 14.4g of water (H2O) are produced. Additionally, the relative density of the alkene with respect to air is given as 1.93.

To determine the molecular formula of the alkene, we can follow these steps:

1. Calculate the moles of carbon dioxide (CO2) produced: - The molar mass of carbon dioxide (CO2) is 44.01 g/mol. - Therefore, the number of moles of CO2 produced is 35.2g / 44.01 g/mol.

2. Calculate the moles of water (H2O) produced: - The molar mass of water (H2O) is 18.02 g/mol. - Therefore, the number of moles of H2O produced is 14.4g / 18.02 g/mol.

3. Determine the empirical formula of the alkene: - The empirical formula represents the simplest whole-number ratio of atoms in a compound. - To find the empirical formula, we need to divide the number of moles of each element by the smallest number of moles obtained. - In this case, we divide the number of moles of carbon dioxide and water by the smallest number of moles obtained.

4. Calculate the molar mass of the empirical formula: - The molar mass of the empirical formula can be calculated by summing the atomic masses of all the atoms in the empirical formula.

5. Determine the molecular formula of the alkene: - The molecular formula represents the actual number of atoms of each element in a compound. - To find the molecular formula, we need to determine the ratio between the molar mass of the empirical formula and the molar mass of the alkene.

Unfortunately, the given information does not provide the necessary data to calculate the molecular formula of the alkene. The relative density of the alkene with respect to air does not directly provide information about the molecular formula.

If you have any additional information or if there is anything else I can help you with, please let me know!