 So let's try this problem now So let's figure out what the energy of a photon would be if it's wavelength is 589 nanometers so we saw this with our glowing pickle or With like the light coming from a sodium D-Wing. Okay, so remember Planck's equation is the way to do this so E equals N H being Planck's constant and new being the frequency Okay, so remember that also so we don't have New or energy given to us, so we're gonna have to figure one of those things out, right? So we have wavelength given to us and if we recall the speed of light equation, which we which says speed of light equals lambda times new or wavelength times frequency We should be able to take this equation rearrange it for Frequency and plug it into this equation here. Okay, so let's do that So frequency equals speed of light divided by lambda So everybody can do that So now Frequency there and frequency there of course are the same thing so what we're going to do is plug one in for the other so email equals N H C over lambda. Okay, so we should have all of these things so what did it say? It said one photon right so N in this case Is going to be one so does everybody okay with that so now all we really have to do is plug and chuck, right? so 26 Remember just like what we did with the other one we can if you have any trouble with this we can Take this and do one over wavelength here. So the wavelength is five hundred and 89 nanometers, and I guess I should have converted at the beginning, but we're going to convert at the end now So everybody knows and is one I can erase it. So how do I convert from nanometers to meters well one Times 10 to the ninth So nanometers cancelled meters cancelled seconds cancels Leaving us with joules is joules a proper energy unit guys Yes, I wasn't a very confident. Yes, is it? Yeah, right, right? That's the best energy unit that we know by this point So let's get our answer and I should expect this to be a small number Right, because we're thinking about one photon in particular It's the three sig figs because that's what our wavelength was So I got three point three seven times ten to the negative For one photo Okay, so this problem also has a part of B and it asks us Well, how many joules would it be per mole of photons at five hundred and eighty nine nanometers, okay? So let's do this for right now, and then we'll figure out what it would be for a mole Okay, so now that everybody's written this down the only difference would be what anybody tell me Yeah, so and would change from one 6.0 22 times 10 to the 23rd So if we do that can I raise parts of it? I'm just gonna rate parts of it So I don't have to rewrite the whole thing and be that same number just like what was said times Avogadro's number 6.0 22 Hopefully you expect to be a very big note. Okay, especially in joules since that's a small Unit, and I got zero or two point zero three Times ten to the one two three four five per mole of these photos Remember write it down Question