Calculate the mass of O2 produced of 3.450g potassium chlorate is completely decolmposed by heating in the presence of a catalyst (Magnese dioxide).
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To calculate the mass of oxygen gas (O2) produced when 3.450 g of potassium chlorate (KClO3) is completely decomposed by heating in the presence of a catalyst (manganese dioxide), we need to determine the stoichiometry of the reaction.
The balanced equation for the reaction is:
2KClO3 → 2KCl + 3O2
From this equation, we can see that for every 2 moles of KClO3 decomposed, 3 moles of O2 are produced.
1. Calculate the molar mass of KClO3:
Molar mass of K: 39.10 g/mol
Molar mass of Cl: 35.45 g/mol
Molar mass of O: 16.00 g/mol
Molar mass of KClO3 = (39.10 g/mol) + (35.45 g/mol) + (3 * 16.00 g/mol)
= 39.10 g/mol + 35.45 g/mol + 48.00 g/mol
= 122.55 g/mol
2. Convert the mass of KClO3 to moles:
Moles of KClO3 = Mass of KClO3 / Molar mass of KClO3
= 3.450 g / 122.55 g/mol
= 0.0282 mol
3. Using the stoichiometry of the balanced equation, determine the moles of O2 produced:
Moles of O2 = (Moles of KClO3) * (3 moles of O2 / 2 moles of KClO3)
= 0.0282 mol * (3 mol O2 / 2 mol KClO3)
= 0.0423 mol
4. Convert the moles of O2 to mass:
Mass of O2 = (Moles of O2) * (Molar mass of O2)
= 0.0423 mol * 32.00 g/mol
= 1.35 g
Therefore, the mass of O2 produced when 3.450 g of potassium chlorate is completely decomposed is 1.35 g.
To calculate the mass of O2 produced when potassium chlorate (KClO3) is decomposed, we need to use stoichiometry. The balanced equation for the reaction is:
2 KClO3(s) -> 2 KCl(s) + 3 O2(g)
From the equation, we can see that for every 2 moles of KClO3 decomposed, 3 moles of O2 are produced.
Step 1: Convert the given mass of potassium chlorate to moles.
To do this, we need to find the molar mass of KClO3. The molar mass of K is 39.1 g/mol, Cl is 35.45 g/mol, and O is 16.00 g/mol.
Molar mass of KClO3 = (39.1 g/mol) + (35.45 g/mol) + (3 * 16.00 g/mol) = 122.55 g/mol
Now, we can calculate the number of moles of KClO3:
Moles of KClO3 = Mass of KClO3 / Molar mass of KClO3
= 3.450 g / 122.55 g/mol
Step 2: Calculate the moles of O2 produced using the mole ratio.
Since the mole ratio between KClO3 and O2 is 2:3, we can calculate the moles of O2 produced:
Moles of O2 = (Moles of KClO3) x (3 moles of O2 / 2 moles of KClO3)
Step 3: Convert moles of O2 to grams.
Now, we can convert the moles of O2 to grams using the molar mass of O2, which is 32.00 g/mol.
Mass of O2 = (Moles of O2) x (Molar mass of O2)
Finally, plug in the values:
Moles of KClO3 = 3.450 g / 122.55 g/mol
Moles of O2 = (Moles of KClO3) x (3 moles of O2 / 2 moles of KClO3)
Mass of O2 = (Moles of O2) x (Molar mass of O2)
And calculate to find the mass of O2 produced.