A compound of chlorine and fluorine, ClFn, reacts at about 75oC with uranium metal to produce uranium hexafluoride, UF6 and chlorine monofluoride, ClF (g). A quantity of uranium produced 3.53g UF6 and 343 mL ClF at 75oC and 2.50 atm. What is the formula (n) of the compound?

Use PV = nRT to caluclate mols ClF from the 343 mL value. I obtained 0.03.

Use mols = grams/molar mass to determine mols UF6. I obtained 0.01.

Then U + ClFn ==> UF6 + xClF
.........0.03...0.01...0.03
You have 0.06 mols F in 0.01 mols UF6
(6 mols F/mol UF6) x (0.03/0.06) = 3 mols F/mol ClF; therefore, x = 3 and that makes the left side have 9 F. Put that together to obtain
U + 3ClF3 ==> UF6 + 3ClF

To determine the formula (n) of the compound ClFn, we need to use the information given.

First, let's convert the volume of chlorine monofluoride (ClF) from milliliters (mL) to liters (L):

343 mL = 343/1000 L = 0.343 L

Next, we need to calculate the number of moles of chlorine monofluoride (ClF) using the ideal gas law:

PV = nRT

Where:
P = pressure = 2.50 atm
V = volume = 0.343 L
n = number of moles (unknown)
R = ideal gas constant = 0.0821 L·atm/(mol·K)
T = temperature = 75 + 273.15 K (converted from oC to K)

Plugging in the values, we can solve for n:

(2.50 atm) * (0.343 L) = n * (0.0821 L·atm/(mol·K)) * (75 + 273.15 K)

0.8575 = n * 20.871

n = 0.04115 moles

Now, let's calculate the number of moles of uranium hexafluoride (UF6) produced using the given mass:

Mass of UF6 = 3.53 g

To find the number of moles, we divide the mass by the molar mass. The molar mass of UF6 is calculated as follows:

(1 * atomic mass of U) + (6 * atomic mass of F)

(1 * 238.03 g/mol) + (6 * 18.998 g/mol) = 349.03 g/mol

Number of moles of UF6 = (3.53 g) / (349.03 g/mol) = 0.0101 moles

Finally, we can determine the value of n in ClFn from the mole ratio between ClF and UF6:

From the equation: ClFn + U → UF6 + ClF

The coefficient of ClF is 1, indicating a 1:1 mole ratio between ClFn and ClF.

Since 0.0101 moles of UF6 react to produce 0.0101 moles of ClF, this implies that the compound ClFn has a formula of ClF1.

Therefore, the formula (n) of the compound ClFn is ClF1.

To determine the formula (n) of the compound ClFn, we can use the given information about the reaction between ClFn, uranium metal, and the products UF6 and ClF.

First, let's use stoichiometry to calculate the number of moles of UF6 and ClF produced. We can then compare these quantities to find the ratio of moles between chlorine and fluorine atoms.

1. Calculate the number of moles of UF6:
- Given mass of UF6 = 3.53 g
- Molar mass of UF6 = atomic mass of U + 6(atomic mass of F) = (238.03 g/mol) + 6(18.99 g/mol) = 352.02 g/mol
- Number of moles of UF6 = given mass / molar mass = 3.53 g / 352.02 g/mol = 0.01 mol

2. Calculate the number of moles of ClF:
- Given volume of ClF gas = 343 mL = 0.343 L
- Given pressure of ClF gas = 2.50 atm
- Given temperature of the reaction = 75°C = 348 K (convert to Kelvin)
- Ideal Gas Law: PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is the temperature.
- Rearrange the equation to solve for n: n = PV / RT
- Gas constant, R = 0.0821 L·atm/(mol·K)
- Number of moles of ClF = (2.50 atm) × (0.343 L) / (0.0821 L·atm/(mol·K) × 348 K) = 0.034 mol

3. Calculate the mole ratio of Cl to F:
- From the balanced chemical equation, the reaction produces 1 mol UF6 and 1 mol ClF.
- Therefore, the ratio of moles of Cl to F is 1:1.

Therefore, the formula (n) of the compound ClFn is ClF, indicating that the compound consists of one atom of chlorine (Cl) and one atom of fluorine (F).