Question

При спалюваннi 9,81г вуглеводню утворилось 30,83г карбона 4 оксиду i 12,61 г води. Визначити молекулярну формулу речовини, якщо вiдносна гусятина за азотом дорiвнюэ 4,5.

Answer 1

Ответ:

C9H18

Объяснение:

Массы составных элементов

С - (30,83/44)*12=8,4

H - (12.61/18)*2=1,4

Отношение к массе сгоревшего с учетом молярных масс

С - ((8,4/9,81)*28*4,5)/12=9

H - (1.4/9.81)*28*4.5=18

M(C9H18)=4.5*28=126 г/моль

Answer 2

Chemical Equation and Calculation

To determine the molecular formula of the substance, we can start by examining the chemical equation for the reaction. The given information states that 9.81g of a hydrocarbon produced 30.83g of carbon dioxide and 12.61g of water when burned. The reaction can be represented as:

C_xH_y + O₂ → CO₂ + H₂O

Calculation of Moles

First, we need to calculate the moles of each substance involved in the reaction. We can use the molar masses of carbon and hydrogen to do this.

The molar mass of carbon (C) is approximately 12.01 g/mol, and the molar mass of hydrogen (H) is approximately 1.008 g/mol.

1. Moles of carbon dioxide (CO₂): - Moles = Mass / Molar mass - Moles of CO₂ = 30.83g / 44.01g/mol

2. Moles of water (H₂O): - Moles of H₂O = 12.61g / 18.015g/mol

3. Moles of carbon (C) in the hydrocarbon: - Moles of C = 30.83g / 12.01g/mol

4. Moles of hydrogen (H) in the hydrocarbon: - Moles of H = 12.61g / 1.008g/mol

Determining the Empirical Formula

Next, we can determine the empirical formula of the hydrocarbon by finding the simplest whole number ratio of moles of carbon to moles of hydrogen.

5. Calculate the moles of carbon and hydrogen in the hydrocarbon. 6. Divide the moles of each element by the smallest number of moles calculated.

Calculation of Relative Atomic Ratios

Given that the relative atomic ratio for nitrogen is 4.5, we can use this information to determine the molecular formula of the substance.

7. Calculate the relative atomic ratio for the hydrocarbon using the given information.

By following these steps, we can determine the molecular formula of the substance based on the given data.