Nuclear Energy

Recall:

Recall: Energy transformations come in two main types

Recall: Energy transformations come in two main types Energy type  energy type (e.g. kinetic  potential)

Recall: Energy transformations come in two main types Energy type  energy type (e.g. kinetic  potential) Energy  Mass

Recall: Energy transformations come in two main types Energy type  energy type (e.g. kinetic  potential) Mass  Energy For the rest of the unit, this is the energy transformation we are referring to

Nuclear energy Energy transformations come in two main types Energy type  energy type (e.g. kinetic  potential) Mass  Energy Nuclear energy, on the other hand, comes from transforming mass into energy

Nuclear energy Nuclear energy is produced through nuclear reactions

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions:

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged Bonds are broken/formed

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged Bonds are broken/formed The number and type of atoms at the beginning of the reaction are the same at the end

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged Bonds are broken/formed The number and type of atoms at the beginning of the reaction are the same at the end Example: 2 𝐻 2 + 𝑂 2 →2 𝐻 2 𝑂

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged Bonds are broken/formed The number and type of atoms at the beginning of the reaction are the same at the end Example: 2 𝐻 2 + 𝑂 2 →2 𝐻 2 𝑂 Nuclear reactions:

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged Bonds are broken/formed The number and type of atoms at the beginning of the reaction are the same at the end Example: 2 𝐻 2 + 𝑂 2 →2 𝐻 2 𝑂 Nuclear reactions: The nucleus of atoms are changed

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged Bonds are broken/formed The number and type of atoms at the beginning of the reaction are the same at the end Example: 2 𝐻 2 + 𝑂 2 →2 𝐻 2 𝑂 Nuclear reactions: The nucleus of atoms are changed The number and type of atoms at the beginning of the reaction are different from those at the end

Nuclear energy Nuclear energy is produced through nuclear reactions Nuclear reactions are very different from chemical reactions Chemical reactions: Atoms are rearranged Bonds are broken/formed The number and type of atoms at the beginning of the reaction are the same at the end Example: 2 𝐻 2 + 𝑂 2 →2 𝐻 2 𝑂 Nuclear reactions: The nucleus of atoms are changed The number and type of atoms at the beginning of the reaction are different from those at the end Example: 4𝐻→2𝐻𝑒

Nuclear reactions Nuclear energy can be created through two types of nuclear reactions Fission Fusion

Nuclear reactions Nuclear energy can be created through two types of nuclear reactions Fission: breaking apart a large atom into several small atoms, releasing energy Fusion

Nuclear reactions Nuclear energy can be created through two types of nuclear reactions Fission: breaking apart a large atom into several small atoms, releasing energy Fusion: combining two small atoms to form one larger atom, releasing energy

Fission reactions When a large atom is split into two or more smaller atoms, releasing energy

Fission reactions When a large atom is split into two or more smaller atoms, releasing energy Example: Uranium + neutron  barium + krypton + 3 neutrons + energy

Uranium + neutron  barium + krypton + 3 neutrons + energy

Uranium + neutron  barium + krypton + 3 neutrons + energy

Uranium + neutron  barium + krypton + 3 neutrons + energy The mass of reactants (uranium and one neutron) is actually greater than the mass of the products (barium, krypton, and neutrons)

Uranium + neutron  barium + krypton + 3 neutrons + energy The mass of reactants (uranium and one neutron) is actually greater than the mass of the products (barium, krypton, and neutrons) The mass lost over the course of this reactions is converted into energy according to the equation: 𝐸=𝑚 𝑐 2

Uranium + neutron  barium + krypton + 3 neutrons + energy The mass of reactants (uranium and one neutron) is actually greater than the mass of the products (barium, krypton, and neutrons) The mass lost over the course of this reactions is converted into energy according to the equation: 𝐸=𝑚 𝑐 2 Fission reaction of one atom of uranium:

Uranium + neutron  barium + krypton + 3 neutrons + energy The mass of reactants (uranium and one neutron) is actually greater than the mass of the products (barium, krypton, and neutrons) The mass lost over the course of this reactions is converted into energy according to the equation: 𝐸=𝑚 𝑐 2 Fission reaction of one atom of uranium: m = mass = 3.6 x 10 −28 kg

Uranium + neutron  barium + krypton + 3 neutrons + energy The mass of reactants (uranium and one neutron) is actually greater than the mass of the products (barium, krypton, and neutrons) The mass lost over the course of this reactions is converted into energy according to the equation: 𝐸=𝑚 𝑐 2 Fission reaction of one atom of uranium: m = mass = 3.6 x 10 −28 kg c = speed of light in a vacuum = 3.0 x 10 8 m/ 𝑠 2

Uranium + neutron  barium + krypton + 3 neutrons + energy The mass of reactants (uranium and one neutron) is actually greater than the mass of the products (barium, krypton, and neutrons) The mass lost over the course of this reactions is converted into energy according to the equation: 𝐸=𝑚 𝑐 2 Fission reaction of one atom of uranium: m = mass = 3.6 x 10 −28 kg c = speed of light in a vacuum = 3.0 x 10 8 m/ 𝑠 2 E = (3.6 x 10 −28 ) (3.0 x 10 8 ) 2 = 3.2 x 10 −11 Joules

Uranium + neutron  barium + krypton + 3 neutrons + energy This may not seem like a lot of energy but:

Uranium + neutron  barium + krypton + 3 neutrons + energy This may not seem like a lot of energy but: A 747 requires 720,000,000,000 J of energy

Uranium + neutron  barium + krypton + 3 neutrons + energy This may not seem like a lot of energy but: A 747 requires 720,000,000,000 J of energy If we used fission to power the 747 we would only need 8.7g of uranium!!!!

Fission reactions Nuclear power plants use fission reactions to produce electricity Homer saves the day

Fission reactions Nuclear power plants use fission reactions to produce electricity Atomic bombs are powered by fission reactions https://www.youtube.com/watch?v=RqyBzXYZPoM

Fusion reactions When two small atoms are combined to form one larger atom, releasing energy

Fusion reactions When two small atoms are combined to form one larger atom Example: 4H  2He + energy

Fusion reactions When two small atoms are combined to form one larger atom Example: 4H  2He + energy The mass of the reactants (hydrogen) is greater than the products (helium)

Fusion reactions When two small atoms are combined to form one larger atom Example: 4H  2He + energy The mass of the reactants (hydrogen) is greater than the products (helium) Over the course of this reaction, the overall mass decreases by 2.8 x 10 −29 kg

Fusion reactions When two small atoms are combined to form one larger atom Example: 4H  2He + energy The mass of the reactants (hydrogen) is greater than the products (helium) Over the course of this reaction, the overall mass decreases by 2.8 x 10 −29 kg According to our equation 𝐸=𝑚 𝑐 2 , this reaction produces: E = (2.8 x 10 −28 ) (3.0 x 10 8 ) 2 = 2.5 x 10 −11 Joules

Fusion reactions When two small atoms are combined to form one larger atom Example: 4H  2He + energy The mass of the reactants (hydrogen) is greater than the products (helium) Over the course of this reaction, the overall mass decreases by 2.8 x 10 −29 kg According to our equation 𝐸=𝑚 𝑐 2 , this reaction produces: E = (2.8 x 10 −28 ) (3.0 x 10 8 ) 2 = 2.5 x 10 −11 Joules In order to power a 747 jet you would only need 0.19g of hydrogen!!

Fusion reactions Fusion reactions produce about 4x more energy than fission reactions

Fusion reactions Fusion reactions produce about 4x more energy than fission reactions Fusion reactions power the sun (and therefore the Earth)

Fusion reactions Fusion reactions produce about 4 x more energy than fission reactions Fusion reactions power the sun (and therefore the Earth) We have not been able to harness the power of fusion reactions to produce electricity

Fusion reactions Fusion reactions produce about 4 x more energy than fission reactions Fusion reactions power the sun (and therefore the Earth) We have not been able to harness the power of fusion reactions to produce electricity Require high temperature and pressure

Fusion reactions Fusion reactions produce about 4 x more energy than fission reactions Fusion reactions power the sun (and therefore the Earth) We have not been able to harness the power of fusion reactions to produce electricity Require high temperature and pressure The invention of ‘cold fusion’ would revolutionize energy production

Fusion reactions Fusion reactions produce about 4 x more energy than fission reactions Fusion reactions power the sun (and therefore the Earth) We have not been able to harness the power of fusion reactions to produce electricity Require high temperature and pressure The invention of ‘cold fusion’ would revolutionize energy production H-bombs are powered by fusion reactions (a fission reaction contributes the energy to initiate the fusion reaction) https://www.youtube.com/watch?v=qjnm3V0xYjI