Nuclear Reactions Nuclear Reactions.

Nuclear Reactions

Nuclear Reactions

Do Now1.What is the ratio range necessary

for an atom to be stable?

2.What ratio is needed for atoms with small atomic numbers to be stable?

3.If an element had 65 protons, how many neutrons would be a good number for it to have in order to be stable?

Nuclear ReactionsEssential Questions: How do nuclear reactions help to stabilize an atom’s nucleus?

Nuclear Reactions

• A nuclear reaction is a reaction that changes the amount of particles in the nucleus of an atom.

What is a nuclear reaction?

Nuclear Reactions

• These reactions happen spontaneously as unstable nuclei release either protons, neutrons or both in an attempt to become stable.

These nuclear reactions happen spontaneously.

Why?

Nuclear Reactions

During this process, the nuclei give off large amounts of energy and are able to increase their stability.

What happens as a result of the nucleus releasing nucleons (protons and neutrons)?

Stop and Think1)Why would a nuclei be unstable?2)Explain why a nuclear reaction would happen

spontaneously?3)What are the end results of a spontaneous nuclear

reaction?

Nuclear ReactionsWhat is the difference between a nuclear reaction and a chemical reaction?• Chemical reactions involve an atom’s

electrons• Nuclear reactions involve the atom’s

nucleus. Chemical reaction

Nuclear reaction

Writing a Nuclear Reaction Equation

In order to write an equation for a nuclear reaction, we must first remember some basic rules. Each of the elements involved in the reaction is identified by the chemical or nuclear symbol.The number at the upper right is theMass number

The number in the lower right is the

Atomic number

Stop and Think1.Give two reasons why the mass number is so important.

2.What information can be found from the atomic number?

3.How do both numbers help to determine the stability of an atom?

Symbols Used in Nuclear Reactions

The symbol for an alpha particle =

The symbol for a beta particle is The symbol for a positron (positive beta particle) is

The chemical symbol for a neutron =

Balancing Nuclear Reactions• When a nuclear reaction

occurs, the total number of atomic numbers, and the total number of mass numbers must be equal on both sides of the equation

TransmutationNotice that when the atomic number changes, the identity of the element changes. This is called transmutation which is a change in the identity of a nucleus as a result of a change in the number of protons.

Stop and Think1.Why must the total number of mass numbers and atomic numbers

be the same on both sides of a nuclear equation?

2.How can you identify the new product created as a result of a nuclear reaction?

Balancing Nuclear reaction Practice