ShmoopTube

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Here's your shmoop du jour brought to you by prizefights [Men in boxing ring]

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which create a real dilemma for us because while we hate fighting but we

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love prizes so if we need to we'll punch a box of Cracker Jacks or just get that [Girl punches box of cracker jacks]

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price and don't you think we want our heavyweight prizefight for most stable

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nucleus has been highly contested with nickel 62 and iron 56 duking it out as

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the top two contenders while it's true that iron 56 has the lowest mass per [Iron 56 and nickel 62 in a boxing ring]

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nucleon nickel 62 with the highest value of binding energy per nucleon of any

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nuclei has ultimately been declared the winner well given that the mass of a

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nucleus is 61 point 9 13 you what is the approximate value of nickel 62 s binding

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energy per nucleon and more essential answers....

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alright well we know that particles with like charges repel each other but in an [Particles with positive charge]

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atom's nucleus there are protons which all have a positive charge and neutrons

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well which don't have any charge why are they all together it's because of the

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strong force that's what binds nucleons and allows all the different elements in

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the universe to form without the strong force there would only be hydrogen atoms [Hydrogen atoms at a bar]

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which would make the universe pretty boring in order to hold the particles

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together the strong force converts some of the mass of the nucleons into energy

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well this means that the actual mass of the nucleus is less than the total mass

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of the nucleons the difference between the expected mass and the real mass is

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called the mass defect enough that we're saying nuclear defective it's nothing [Atoms appear angry on side street]

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personal Einstein gave us the equation to calculate how much energy is created

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by this loss of mass and yet it's the most famous equation in the world e

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equals MC squared it means that energy equals mass times the speed of light

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squared so it doesn't take much mass to create a whole lot of energy to answer [Dynamite explodes on road]

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this question first we need to figure out how much mass is missing well nickel

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has an atomic number of 28 meaning there are 28 protons in [Nickel electron shells appear]

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each proton has a mass of 1.00 732 atomic mass units well since this

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isotope has a mass number of 62 we can find the number of neutrons by

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subtracting the protons from the mass number well neutrons are just a little [Neutron appears]

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bit chubbier than their proton cousins they have a mass of 1.00 867 you /

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neutron so they add up to 34.295 you got it all right when we add the

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protons and neutrons we find an expected mass of 62.5 you to find the mass defect

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we just subtract the actual mass from the expected mask that now we can

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convert the mass to energy one atomic mass unit equals 931 mega electron volts [Atomic mass unit appears]

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we multiply the mass defect by 931 math to find a binding energy of 540 9.29 med

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alright well now let's take a look back at the question because by now we've [Man looking through paper]

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pretty much forgotten why we're doing all this oh yeah we need to find the

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binding energy per nucleon well there are 62 nucleons so we divide the binding

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energy by that number the binding energy per nucleon is about 8.9 mega electron [Binding energy equation appears]

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volts so the correct answer is B the strong force only acts on a very tiny

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scale that it's the strongest force in the universe which makes sense as we saw

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here a tiny amount of mass creates a large amount of energy and the strong

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force is able to completely overcome the electromagnetic force that pushes the

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protons away from each other and remember that violence is never the [Man trying to open snack pack]

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answer unless our snack won't open then we might just lose it

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