how many molecules of Xef6 are formed from 12.9L at 298K and 2.6atm according to the following reaction. assume excess is Xe

You didn't include the reaction.

To determine the number of molecules of XeF6 formed, we need to use the Ideal Gas Law equation and stoichiometry.

1. Write the balanced chemical equation for the reaction.

Since it is mentioned that excess is Xe, we assume that Xe is not involved in the reaction. So the reaction can be simplified as follows:

2 F2 + 6 XeF6 → 12 XeF2

2. Use the Ideal Gas Law equation to calculate the number of moles of XeF2 produced.

PV = nRT

P = pressure (2.6 atm)
V = volume (12.9 L)
n = number of moles of XeF2
R = ideal gas constant (0.0821 L•atm/mol•K)
T = temperature (298 K)

Rearranging the equation, we get:

n = PV / RT

n = (2.6 atm * 12.9 L) / (0.0821 L·atm/mol·K * 298 K)
n = 4.08 moles of XeF2

3. Use stoichiometry to convert moles of XeF2 to molecules of XeF6.

From the balanced equation, we see that 6 moles of XeF6 are formed for every 12 moles of XeF2.

So, the ratio is 6 moles of XeF6 / 12 moles of XeF2.

To calculate the moles of XeF6 formed:

moles of XeF6 = (4.08 moles of XeF2) * (6 moles of XeF6 / 12 moles of XeF2)
moles of XeF6 = 2.04 moles of XeF6

4. Finally, convert moles of XeF6 to molecules using Avogadro's number.

1 mole of any substance contains 6.02 x 10^23 molecules.

So, number of molecules of XeF6 = (2.04 moles of XeF6) * (6.02 x 10^23 molecules/mole)
number of molecules of XeF6 = 1.23 x 10^24 molecules of XeF6

Therefore, approximately 1.23 x 10^24 molecules of XeF6 are formed.