I have no clue as to how this problem should be solved... could i have some help please?
Calculate the rms speed of SF6 molecules at 16°C
The formula is in your text, I'm sure. Look under Kinetic Molecular Theory.
rms = sqrt(3RT/M) where R is 8.314, T is is Kelvin and M is molar mass.
thanks
so is it
3 x 8.314 x (16°C + 273)K / (146.065 molecules / 6.02e23) = 2.970841253e25 ?
is that right?
No. You have omitted the square root AND you stuck a 6.02e23 in there that doesn't belong there.
rms = sqrt(3*8.314*289/146.056) = ??
The M is the molar mass; i.e., the mass of 1 mol which is 146.056g (not 146.065 molecules).
ok so...
sqrt(3 x 8.314 x 289/146.056) = 7.025 m/s
is that right?
That's what I have. If your prof is picky about significant figures, I would round the 7.025 to 7.02 m/s (three places since the 289 is to 3 places).
Certainly! I can help you with that. To calculate the root mean square (rms) speed of SF6 molecules at a given temperature, you can use the following equation:
vrms = √((3 * k * T) / m)
Where:
- vrms is the rms speed
- k is the Boltzmann constant (1.38 × 10^-23 J/K)
- T is the temperature in Kelvin (16°C + 273 = 289 K)
- m is the molar mass of SF6 (you can find this in the periodic table)
First, let's find the molar mass of SF6. Sulfur (S) has an atomic mass of approximately 32.06 g/mol, and each fluorine (F) has an atomic mass of approximately 18.998 g/mol. Multiply the atomic mass of each element by the number of atoms present in SF6 and add them up:
Molar mass of SF6 = (1 * Molar mass of S) + (6 * Molar mass of F)
Molar mass of SF6 = (1 * 32.06 g/mol) + (6 * 18.998 g/mol)
Now that we have the molar mass of SF6, let's substitute the values into the rms speed equation:
vrms = √((3 * k * T) / m)
vrms = √((3 * (1.38 × 10^-23 J/K) * 289 K) / Molar mass of SF6)
By plugging in the values, you can calculate the rms speed of SF6 molecules at 16°C.