What is the volume occupied by 20.2g NH3(g) at -25 degrees celsius and 752 mmHg?

This is Ideal Gas Law.

To find the volume occupied by a gas, we can use the Ideal Gas Law, which is represented by the equation:

PV = nRT

Where:
P = pressure of the gas
V = volume occupied by the gas
n = number of moles of the gas
R = ideal gas constant
T = temperature of the gas in Kelvin

Let's break down the given information:

- Pressure (P) = 752 mmHg
- Temperature (T) = -25 degrees Celsius

To use the Ideal Gas Law, we need to convert the temperature to Kelvin. We can do this by adding 273.15 to the Celsius temperature:

T(K) = T(°C) + 273.15

So, T(K) = -25 + 273.15 = 248.15 K

Now, we need to calculate the number of moles (n) of NH3(g). We can use the molar mass of NH3 to convert the given mass to moles:

Molar mass of NH3(g) = 17.03 g/mol

n = mass / molar mass

n = 20.2 g / 17.03 g/mol ≈ 1.186 mol

Now that we have all the variables, we can rearrange the Ideal Gas Law equation to solve for volume (V):

V = (nRT) / P

Let's substitute the values into the equation:

V = (1.186 mol * 0.0821 L/mol·K * 248.15 K) / 752 mmHg

Note: The ideal gas constant, R, has a value of 0.0821 L/mol·K.

Now we can calculate the volume. To do this, we need to convert mmHg to atmospheres (atm) because the units for R are in atm·L/mol·K:

1 atm = 760 mmHg

V = (1.186 mol * 0.0821 L/mol·K * 248.15 K) / (752 mmHg / 760 mmHg/atm)

V ≈ 0.091 L or 91 mL

Therefore, the volume occupied by 20.2 g of NH3(g) at -25 degrees Celsius and 752 mmHg is approximately 0.091 L or 91 mL.