5.50 grams of nitrogen triiodide are detonated in a closed 7.00 L flask that was under full vacuum initially. The nitrogen triiodide forms nitrogen gas and iodine gas upon detonation. What is the partial pressure of the iodine gas (in Pa) when the vessel cools down to 23 C?

Thanks!

2NI3 ==> N2 + 3I2

5.50 g NI3 = ?? moles. moles = grams/molar mass.

Using the coefficients in the balanced equation, convert moles NI3 to moles N2 and to moles I2. N2 should be 1/2 moles NI3 and I2 should be 3/2 moles NI3.
Then use PV = nRT with new conditions of T etc to calculate P. Post your work if you get stuck.

To find the partial pressure of iodine gas, we need to use the ideal gas law and the stoichiometry of the reaction.

Step 1: Determine the moles of nitrogen triiodide (NI3)
To calculate the moles of NI3, we need to use its molar mass. The molar mass of NI3 is:
N = 14.01 g/mol
I = 126.9 g/mol (3 iodine atoms in NI3)
Total molar mass = 14.01 + (126.9 x 3) = 394.71 g/mol

moles of NI3 = mass of NI3 / molar mass of NI3
moles of NI3 = 5.50 g / 394.71 g/mol

Step 2: Determine the moles of iodine gas (I2) formed
From the balanced chemical equation, we know that 1 mole of NI3 forms 1 mole of I2. Therefore, the moles of I2 will be the same as the moles of NI3.

moles of I2 = moles of NI3

Step 3: Convert moles to volume using the ideal gas law
The ideal gas law is given by: PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant (8.314 J/(mol・K)), and T is the temperature in Kelvin.

First, we need to convert the given volume from liters to cubic meters (m^3):
volume = 7.00 L = 0.007 m^3

Next, we need to convert the temperature from Celsius to Kelvin:
T = 23°C + 273.15 = 296.15 K

Now we can rearrange the ideal gas law to solve for pressure (P):
P = (nRT) / V, where n is the number of moles of I2, R is the ideal gas constant, T is the temperature in Kelvin, and V is the volume.

Substitute the values into the equation:
P = (moles of I2) * (R) * (T) / V

Step 4: Calculate the partial pressure of iodine gas
Substitute the value of moles of I2 into the equation:
P = (moles of I2) * (R) * (T) / V

Finally, calculate the partial pressure in pascals (Pa):
Partial pressure of iodine gas = P * 100,000 Pa (since 1 bar = 100,000 Pa)

By following these steps, you can calculate the partial pressure of iodine gas when the vessel cools down to 23°C.