What is the pressure in millimeters of mercury of 0.0115mol of helium gas with a volume of 211ml at a temperature of 25 degrees celsius?

Ok so I've come up with many different answers but none are right. You convert the mL to L and the temperature to Kelvin by adding 273 right? and you're using PV=NRT? And is the answer in psi so that I need to convert it to mmHg? Sorry, so many question!

questions**

Just kidding. I'm stupid. I converted psi to mmHg and not atm to mmHg instead.

I assume you know what went wrong but I'll play it safe and answer.

Yes, T must be in kelvin, P in atmospheres, V in L. n = grams/molar mass.

No problem, let's break down the steps to find the pressure in millimeters of mercury (mmHg) for the given conditions.

First, convert the volume from milliliters (ml) to liters (L):

V = 211 ml = 211/1000 L = 0.211 L

Next, convert the temperature from Celsius to Kelvin by adding 273:

T = 25°C + 273 = 298 K

Now, we can use the ideal gas law equation, PV = nRT, to find the pressure (P). Rearranging the equation, we have:

P = (nRT) / V

where:
P is the pressure,
n is the number of moles of helium gas,
R is the ideal gas constant, and
T is the temperature in Kelvin.

Given that n = 0.0115 mol, R is 0.0821 L·atm/(mol·K), and T = 298 K, we can substitute these values into the equation:

P = (0.0115 mol * 0.0821 L·atm/(mol·K) * 298 K) / 0.211 L

Now, we can solve for the pressure (P) in atm (atmospheres). Once we have the pressure in atm, we can convert it to mmHg.

To convert atm to mmHg, we multiply by 760 (since 1 atm = 760 mmHg):

P(atm) * 760 = P(mmHg)

Substitute the calculated pressure (P) in atm into this conversion:

P(mmHg) = P(atm) * 760

By following these steps, you can determine the pressure in mmHg for the given conditions of the helium gas.