Question

2. Вивести формулу вуглеводню, якщо унаслідок спалювання 13,8 г цієї речовини добули 26,4 г вуглекислого газу і 16,2 г води. Густина вуглеводню за воднем дорівнює 23. Знайти формулу речовини. Допоможіть будь ласка зробити це завдання потрібно дуже терміново даю 40 балів​

Answer 1

To find the formula of the substance, we need to analyze the given information about the combustion of the substance and the resulting products. Let's break down the problem step by step.

Given Information:

- Mass of the substance burned (m1) = 13.8 g - Mass of carbon dioxide produced (m2) = 26.4 g - Mass of water produced (m3) = 16.2 g - Density of the hydrocarbon relative to water = 23

Step 1: Calculate the moles of carbon dioxide (CO2) produced:

To find the moles of carbon dioxide produced, we need to use the molar mass of carbon dioxide (44 g/mol).

Moles of CO2 (n2) = m2 / molar mass of CO2

Let's calculate it: Moles of CO2 (n2) = 26.4 g / 44 g/mol = 0.6 mol [[1]]

Step 2: Calculate the moles of water (H2O) produced:

To find the moles of water produced, we need to use the molar mass of water (18 g/mol).

Moles of H2O (n3) = m3 / molar mass of H2O

Let's calculate it: Moles of H2O (n3) = 16.2 g / 18 g/mol = 0.9 mol [[1]]

Step 3: Calculate the moles of carbon (C) in the substance:

To find the moles of carbon in the substance, we need to use the moles of carbon dioxide produced (n2) and the stoichiometric ratio between carbon dioxide and carbon.

The balanced equation for the combustion of a hydrocarbon can be written as: CnHm + (n/2)O2 -> nCO2 + (m/2)H2O

From the balanced equation, we can see that for every 1 mole of carbon dioxide produced, there is 1 mole of carbon in the hydrocarbon.

Moles of carbon (nC) = n2

Let's calculate it: Moles of carbon (nC) = 0.6 mol

Step 4: Calculate the moles of hydrogen (H) in the substance:

To find the moles of hydrogen in the substance, we need to use the moles of water produced (n3) and the stoichiometric ratio between water and hydrogen.

From the balanced equation, we can see that for every 1 mole of water produced, there are 2 moles of hydrogen in the hydrocarbon.

Moles of hydrogen (nH) = 2 * n3

Let's calculate it: Moles of hydrogen (nH) = 2 * 0.9 mol = 1.8 mol

Step 5: Determine the empirical formula of the substance:

The empirical formula represents the simplest whole number ratio of atoms in a compound. To find the empirical formula, we need to divide the moles of each element by the smallest number of moles.

Dividing the moles of carbon and hydrogen by the smallest number of moles (0.6 mol), we get: Empirical formula: C1H3

Step 6: Determine the molecular formula of the substance:

To find the molecular formula, we need to know the molar mass of the substance. Unfortunately, the molar mass is not provided in the given information.

Without the molar mass, we cannot determine the molecular formula. The empirical formula (C1H3) represents the simplest ratio of atoms in the compound, but there could be multiple compounds with the same empirical formula.

Therefore, we cannot determine the molecular formula of the substance without additional information.

Please note that the given information does not provide enough data to determine the molecular formula of the substance. Additional information, such as the molar mass of the substance, is required to proceed further.

I hope this explanation helps! If you have any more questions, feel free to ask.