Potassium nitrate decomposes on heating, producing potassium oxide and gaseous nitrogen and oxygen:

4KNO3(s)--> 2K2O(s) + 2N2(g) + 5O2(g)
To produce 56.6 kg of oxygen, how many (a) moles of KNO3 must be heated? (b) Grams of KNO3 must must heated?

To determine the number of moles of KNO3 needed to produce a specific amount of oxygen, we'll use the stoichiometry of the balanced chemical equation.

(a) Moles of KNO3:
From the balanced equation, the molar ratio between KNO3 and O2 is 4:5. This means that for every 4 moles of KNO3, we obtain 5 moles of O2.

To calculate the moles of KNO3, we'll set up a proportion:

4 moles KNO3 / 5 moles O2 = x moles KNO3 / 56.6 kg O2

First, convert the given mass of O2 to moles:

56.6 kg * (1000 g / 1 kg) * (1 mol O2 / 32 g) = 1768.75 mol O2

Now, set up the proportion:

4/5 = x/1768.75

Cross-multiply to solve for x:

5x = 4 * 1768.75
x = (4 * 1768.75) / 5

So, the moles of KNO3 required to produce 56.6 kg of O2 is:

x = 1415 moles

(b) Grams of KNO3:
To find the grams of KNO3, we can use the molar mass of KNO3.

The molar mass of KNO3 is approximately:
(39.10 g/mol) + (14.01 g/mol) + (3 * 16.00 g/mol) = 101.10 g/mol

To calculate the grams of KNO3, we'll use the following formula:

grams = moles × molar mass

grams = 1415 moles × 101.10 g/mol

The grams of KNO3 required to produce 56.6 kg of oxygen is approximately:
grams = 142930 g

To determine the quantities of KNO3 required to produce a specific amount of oxygen, we need to use stoichiometry and the balanced equation provided.

(a) The balanced equation tells us that for every 5 moles of oxygen produced, 4 moles of KNO3 are needed. Since we want to produce 56.6 kg of oxygen, we first need to convert the mass into moles using the molar mass of oxygen.

The molar mass of oxygen (O2) is approximately 32 g/mol. To determine the number of moles, we divide the mass by the molar mass:

56.6 kg = 56,600 g
Number of moles of oxygen = 56,600 g / 32 g/mol = 1768.75 mol

Now, using the stoichiometric ratios from the balanced equation, we can determine the number of moles of KNO3 required:

4 moles of KNO3 is equivalent to 5 moles of oxygen
Thus, the number of moles of KNO3 required = (1768.75 mol * 4 mol) / 5 mol = 1415 mol

Therefore, to produce 56.6 kg of oxygen, we need 1415 moles of KNO3.

(b) To determine the mass of KNO3 required, we can use the molar mass of KNO3, which is approximately 101 g/mol. Using the same approach as above:

Number of moles of KNO3 required = 1415 mol
Mass of KNO3 required = 1415 mol * 101 g/mol = 142,915 g

Therefore, to produce 56.6 kg of oxygen, we need to heat 142,915 grams (142.915 kg) of KNO3.

I worked this same problem a day or so ago. Frankly, I don't think the equation is correct.

Convert 63.7 kg of oxygen to grams. Then use stoichiometry and convert the grams of Oxygen to moles of Oxygen, then moles of KNO3 using the equation.

Calculations: 63.7 kg ---> 63,700 g. Divide by 32 grams of O2, then multiply by (4 moles KNO3/5 moles O2).

For the second part, take your answer from part A, and multiply it by 101.11 grams/mol of KNO3.