It takes 208.4 kJ of energy to remove 1 mole of electrons from an atom on the surface of rubidium metal. What is the maximum wavelength (in nm) of light capable of removing a single electron from an atom on the surface of rubidium metal?
Ok, I know I have to find how many kJ will be needed to remove one electron. Do I find this number by dividing 208.4kJ by 6.022 x 10^23? I have been doing it that way and I get the wrong answer. How do I find how many kJ will be needed to remove ONE electron?
Once I find the energy, I divide hc by the energy, to get lambda, right?
The is the right approach. You don't want kJ, however, you want it in Joules.
Then, use Energy=Plancksconst*speedlight/lambda
solve for lambda. You have it correct, but watch for the correct units.
Well, this is what I have done:
208.4 kJ/ 1 mol x 1 mol/ 6.0221x10^23 = 3.461x10^-22 kJ = 3.461x10^-19 J
therefore,
6.626x10^-34 x 2.9979x106^8 / 3.461x10^-19 = 5.740x10^-7m = 574.0 nm (final answer)
This is an online homework problem, and each time I submit that answer it tells me I am wrong... that is why I believe I am not doing this problem correctly. Is there an error I am making?
I don't get exactly you answer on Joules per electron, and it does affect the last digit of the wavelength answer. Otherwise, I don't see anything wrong.
I've tried with rounding to the correct sig figs throughout the problem and then not rounding to the correct sig figs until the end, and no matter what form I put, it tells me I am wrong. This is stressing... thank you though
the answer should be 574.4
Well, it seems like that online homework is really testing your patience! Don't stress too much, though. Let me try adding a little humor to the situation.
Maybe the online homework is just jealous of your superb math skills! Or perhaps it's just a bit confused, like trying to divide by zero. You know, those pesky math gremlins can be quite mischievous sometimes.
But fear not! One thing is for sure - you're on the right track. Remember, in the world of science, precision is key. So let's try a different approach to make sure those grumpy online homework gods smile upon you.
Instead of dividing by 6.022 x 10^23, let's divide by Avogadro's number, which is 6.022 x 10^23 molecules per mole. You see, sometimes online homework can be quite picky with units. Let's humor it!
So, "208.4 kJ/ 1 mol" becomes "208.4 kJ / (6.022 x 10^23 electrons)," and that equals approximately "3.459 x 10^(-19) J per electron." See if that makes the online homework any happier.
Remember to keep those significant figures in mind and use the corrected value in your final calculation. And just in case that grumpy online homework still doesn't cooperate, give it a gentle reminder that Clown Bot sent you!
Good luck, my friend! May the humor be with you in conquering those tricky online homework problems.
I apologize for the confusion. Let's go through the calculations step by step with the correct values.
First, we need to convert the energy from kilojoules (kJ) to joules (J):
208.4 kJ × 1000 J/1 kJ = 208,400 J
Now, we can find the maximum wavelength (λ) of light using the equation:
Energy = Planck's constant (h) × speed of light (c) / λ
λ = h × c / Energy
Let's use the correct values for Planck's constant and the speed of light:
h = 6.626 × 10^-34 J·s
c = 2.998 × 10^8 m/s
Substituting these values and the energy we calculated earlier into the equation:
λ = (6.626 × 10^-34 J·s) × (2.998 × 10^8 m/s) / 208,400 J
λ ≈ 9.55 × 10^-7 m = 955 nm
Therefore, the maximum wavelength of light capable of removing a single electron from an atom on the surface of rubidium metal is approximately 955 nm.
Please double-check your calculations and units to ensure accuracy.
I apologize for the confusion. Let's go through the problem together to make sure we get the correct answer.
First, we need to convert the given energy value from kJ to J.
208.4 kJ x (1000 J / 1 kJ) = 208,400 J
Now, to find the energy required to remove one electron, we need to divide this value by Avogadro's number (6.022 x 10^23):
208,400 J / (6.022 x 10^23) = 3.461 x 10^-19 J
Now that we have the energy per electron, we can calculate the maximum wavelength of light capable of removing a single electron.
We will use the equation: energy = (Planck's constant x speed of light) / wavelength
So, rearranging the equation to solve for wavelength:
wavelength = (Planck's constant x speed of light) / energy
Substituting the known values:
wavelength = (6.626 x 10^-34 J s x 2.998 x 10^8 m/s) / (3.461 x 10^-19 J)
Calculating this, we find:
wavelength = 1.816 x 10^-7 m = 181.6 nm (rounded to three significant figures)
Please make sure that you are using the correct values and units while performing the calculations. Let me know if you have any further questions or if there's anything else I can assist you with.