A mixture containing KCLO3, K2CO3, KHCO3, and KCL was heated, producing CO2, O2, and H2O (water) gases according to the following equations:
2KCLO3 -> 2KCL + O2
2KHCO3 -> K2O + H2O + 2CO2
K2CO3 -> K2O + CO2
The KCL does not reacnder the conditions of the reaction. If 100.0g of the mixture produces 1.8g of H20, 13.2g of CO2, and 4g of O2, what was the composition of the original mixture?(assume complete decomposition of the mixture)
someone please show me how to do this!
* all O's in the equations stand for oxygen, nothing means 20, its 2O, 2 then oxygen comes after.
To find the composition of the original mixture, we need to determine the amount of each of the four compounds present in the mixture. We can do this by using the given amounts of H2O, CO2, and O2 produced during the reaction.
Let's start by calculating the number of moles of each gas produced:
Moles of H2O: 1.8g / 18.015 g/mol = 0.0999 mol (rounded to 4 decimal places)
Moles of CO2: 13.2g / 44.01 g/mol = 0.2992 mol (rounded to 4 decimal places)
Moles of O2: 4g / 32.00 g/mol = 0.125 mol
From the first equation:
2KCLO3 -> 2KCl + O2
It can be observed that for every 2 moles of KCLO3, 1 mole of O2 is produced. Therefore, the number of moles of KCLO3 in the original mixture is half the moles of O2 produced:
Moles of KCLO3 = 0.125 mol / 2 = 0.0625 mol
From the second equation:
2KHCO3 -> K2O + H2O + 2CO2
For every 2 moles of KHCO3, 1 mole of H2O is produced. Therefore, the number of moles of KHCO3 in the original mixture is half the moles of H2O produced:
Moles of KHCO3 = 0.0999 mol / 2 = 0.0499 mol
From the third equation:
K2CO3 -> K2O + CO2
It can be observed that for every 1 mole of K2CO3, 1 mole of CO2 is produced. Therefore, the number of moles of K2CO3 in the original mixture is the same as the moles of CO2 produced:
Moles of K2CO3 = 0.2992 mol
Now, we can calculate the number of moles of KCl present in the original mixture. Since KCl does not react and is not produced during the reaction, the number of moles of KCl in the original mixture is zero.
Moles of KCl = 0 mol
Finally, we can determine the composition of the original mixture in terms of mass:
Mass of KCLO3 = Moles of KCLO3 * Molar mass of KCLO3
Mass of KHCO3 = Moles of KHCO3 * Molar mass of KHCO3
Mass of K2CO3 = Moles of K2CO3 * Molar mass of K2CO3
Mass of KCl = Moles of KCl * Molar mass of KCl
To calculate the molar masses:
Molar mass of KCLO3 = 122.549 g/mol
Molar mass of KHCO3 = 100.115 g/mol
Molar mass of K2CO3 = 138.205 g/mol
Molar mass of KCl = 74.551 g/mol
Plugging in the known values:
Mass of KCLO3 = 0.0625 mol * 122.549 g/mol = 7.66 g (rounded to 2 decimal places)
Mass of KHCO3 = 0.0499 mol * 100.115 g/mol = 4.99 g (rounded to 2 decimal places)
Mass of K2CO3 = 0.2992 mol * 138.205 g/mol = 41.33 g (rounded to 2 decimal places)
Mass of KCl = 0 mol * 74.551 g/mol = 0 g
Therefore, the composition of the original mixture is:
- KCLO3: 7.66 g
- KHCO3: 4.99 g
- K2CO3: 41.33 g
- KCl: 0 g
Note: The masses are rounded to two decimal places based on the given data, but it is important to keep in mind that the actual values may have more decimal places depending on the accuracy of the molar masses and experimental data.