White phosphorus, P4, spontaneously bursts into flame in oxygen. if 6.5g of white phosphorus reacts with sufficient oxygen to form 11.54g of a phosphorus oxide, what is the empirical formula of this oxide?
you have 0.05246 moles of P4
the 11.54g of oxide contain 5.04 g of oxygen, which is 0.315 moles of O
0.315/0.05246 = 6
That means you get 6 moles of O for every mole of P4
See what you can do with that.
Assuming all of the 6.5 grams P₄ is consumed in an excess of O₂ to produce 11.54 grams PₓOᵥ then …
%P per 100-wt = (6.5g/11.54g)100% = 56.3258% => 56.3258g/30.9738g/mol = 1.8185 mole P
%O per 100-wt = 100% - 56.3258% = 43.6740% => 43.6740g/15.9994g/mol = 2.7297 mole O
P:O Empirical Ratio = 1.8185/1.8185 : 2.7297/1.8185 = (1:1.5) x 2 => 2:3 Empirical Ratio
=> P₂O₃ Empirical Formula
Oh, the fiery white phosphorus! It's like a pyromaniac's dream. Anyway, let's get down to business. To find the empirical formula of the phosphorus oxide, we need to look at the ratio of the elements.
We're given that 6.5g of white phosphorus reacts to form 11.54g of the oxide. So, the mass of oxygen in the oxide is 11.54g - 6.5g = 5.04g.
Now, let's calculate the number of moles for each element. The molar mass of phosphorus (P) is 30.97 g/mol, and the molar mass of oxygen (O) is 16.00 g/mol.
For phosphorus: 6.5g / 30.97 g/mol = 0.210 mol
For oxygen: 5.04g / 16.00 g/mol = 0.315 mol
Next, we need to find the simplest whole-number ratio by dividing both moles by the smallest number of moles (0.210 mol in this case).
Phosphorus: 0.210 mol / 0.210 mol = 1
Oxygen: 0.315 mol / 0.210 mol = 1.5
Since we need whole numbers, let's multiply everything by 2 to get rid of the decimal point.
Phosphorus: 2
Oxygen: 3
Therefore, the empirical formula of the phosphorus oxide is P2O3. And that, my friend, is truly explosive chemistry! Just remember to keep a safe distance.
To determine the empirical formula of the phosphorus oxide, we need to calculate the moles of white phosphorus and the moles of phosphorus oxide formed in the reaction.
Step 1: Calculate the moles of white phosphorus.
We can use the molar mass of white phosphorus to calculate the number of moles.
Molar mass of white phosphorus (P4) = 4 * molar mass of phosphorus (P)
Since the molar mass of phosphorus (P) is approximately 31 g/mol:
Molar mass of white phosphorus (P4) = 4 * 31 g/mol = 124 g/mol
Now we can calculate the moles of white phosphorus:
moles of white phosphorus = mass of white phosphorus / molar mass of white phosphorus
moles of white phosphorus = 6.5 g / 124 g/mol
Step 2: Calculate the moles of phosphorus oxide.
Using the Law of Conservation of Mass, the moles of phosphorus oxide formed will be equal to the moles of white phosphorus reacted.
moles of phosphorus oxide = moles of white phosphorus
Step 3: Determine the empirical formula.
To determine the empirical formula, we need to calculate the ratio of the number of moles of each element in the compound.
Since the empirical formula of phosphorus oxide contains only phosphorus and oxygen, we only need to consider these two elements.
The ratio of moles of phosphorus to moles of phosphorus oxide will give us the subscripts in the empirical formula.
Let's assume the empirical formula of the phosphorus oxide is PxOy.
moles of phosphorus oxide / moles of phosphorus = (moles of P in PxOy) / (moles of P in P4)
moles of phosphorus oxide / moles of phosphorus = y / 4
Since moles of phosphorus oxide = moles of white phosphorus:
moles of phosphorus oxide / moles of phosphorus = 1 / 1
Therefore,
y / 4 = 1 / 1
y = 4
The empirical formula of the phosphorus oxide is P4O4.
To determine the empirical formula of the oxide formed when white phosphorus reacts with oxygen, we need to find the ratio of atoms present in the compound.
Let's start by finding the number of moles of white phosphorus and the phosphorus oxide:
1. Calculate the number of moles of white phosphorus (P4):
- The molar mass of white phosphorus (P4) is 4 * 31.0 g/mol = 124.0 g/mol.
- Using the given mass of white phosphorus (6.5 g), we can calculate the number of moles:
moles of P4 = mass / molar mass = 6.5 g / 124.0 g/mol ≈ 0.0524 mol.
2. Calculate the number of moles of phosphorus oxide using its mass:
- The molar mass of the phosphorus oxide is given as 11.54 g.
- Now, let's find the number of moles:
moles of phosphorus oxide = mass / molar mass = 11.54 g / molar mass.
Given that the empirical formula represents the simplest whole-number ratio of atoms, we can determine the empirical formula by finding the ratio of the moles of phosphorus to oxygen in the compound.
3. Find the ratio of moles of phosphorus to moles of oxygen:
- The empirical formula must have a ratio of phosphorus to oxygen atoms, which should be a whole number ratio.
- To determine this, we need to calculate the moles of oxygen from the moles of phosphorus oxide.
4. Calculate the number of moles of oxygen atoms:
- Since the molar mass of phosphorus (P4) is 31.0 g/mol, each mole of phosphorus reacts with 5 moles of oxygen (O2) to form the phosphorus oxide.
- Therefore, the ratio of moles of phosphorus to oxygen is 1:5.
- The moles of oxygen atoms can be calculated as:
moles of oxygen = moles of phosphorus oxide * 5.
Now that we have the ratio of moles of phosphorus to moles of oxygen, we can find the empirical formula.
5. Determine the empirical formula:
- Divide the moles of phosphorus by the smaller value (either phosphorus or oxygen) to get the ratio.
- Divide the moles of oxygen by the same smaller value.
- If the ratio is not a whole number, multiply both values by a common factor until the ratio becomes a whole number.
Therefore, to find the empirical formula, you need to calculate the molar mass of the phosphorus oxide and convert the masses to moles, find the ratio of moles of phosphorus to oxygen, and adjust the ratio to its simplest form.