2KClO3 --> 2KCl + 3O2
What mass of O2 can be made from heating 125 g of KClO3?
I know that the answer is 49 g O2 but I keep getting a completely different answer, can anyone show me what I'm doing wrong?
Please & Thank you
If you will post your work I will find your error.
125g KClO3 x (2 mol KClO3/ 122.49g KClO3) = 2.04 mol KClO3
2.04 mol KClO3 x (3 mol O2/1 mol KClO3) =6.12 mol O2
6.12 mol O2 x(31.98g O2/1 mol O2) = 195.71 g O2
See my response to your later post.
To calculate the mass of oxygen (O2) produced from the decomposition of potassium chlorate (KClO3), we need to use stoichiometry and the molar mass of the substances involved.
First, let's start by calculating the molar mass of KClO3:
- K: 39.10 g/mol
- Cl: 35.45 g/mol
- O: 16.00 g/mol (x3 since there are three oxygen atoms in KClO3)
Molar mass of KClO3 = (39.10 g/mol) + (35.45 g/mol) + (16.00 g/mol x 3) = 122.55 g/mol
Now, we can set up the stoichiometric ratio between KClO3 and O2 from the balanced equation:
- 2 moles of KClO3 produce 3 moles of O2
Next, convert the mass of KClO3 given (125 g) to moles:
Moles of KClO3 = Mass of KClO3 / Molar mass of KClO3
Moles of KClO3 = 125 g / 122.55 g/mol
Calculate the moles of O2 produced using the stoichiometric ratio:
Moles of O2 = Moles of KClO3 x (3 moles O2 / 2 moles KClO3)
Finally, convert the moles of O2 to grams using the molar mass of O2:
Mass of O2 = Moles of O2 x Molar mass of O2
Mass of O2 = Moles of O2 x (32.00 g/mol)
By following this calculation process, you should obtain the correct answer of 49 g of O2 produced.
If you obtained a different result, check your calculations for any errors in converting between units, using the correct molar masses, and applying the stoichiometric ratio correctly.