Alchemy Investigation IV-Lesson 2 It’s Greek to Me Alchemy Investigation IV-Lesson 2

Remember from yesterday….. Atoms of the same element will ALWAYS have the same number of protons Isotopes: atoms of the same element with different numbers of neutrons Isotopes have different masses Atomic weight: the weighted average atomic mass of the naturally occurring isotopes (the # on the periodic table)

The above can also be written as: cobalt-59 Isotope notation: The above can also be written as: cobalt-59 Mass number Atomic number

Isotope Notation Practice How many protons does this atom have? What is the mass number for this atom? How many neutrons does this atom have?

ChemCatalyst Uranium-238 is used in nuclear reactors to generate electricity. In the nuclear reactor, uranium-238 changes to lead-209. How can atoms of uranium-238 change into atoms of lead-209? The nuclear reaction is initiated by colliding the uranium-238 with . What do you think this symbol represents?

Nuclear Reactions When the nucleus of an atom is unstable, it will spontaneously decay and the nucleus will emit particles. A change like this in the nucleus of an atom is called a nuclear reaction.

Types of Decay There are 2 types of decay you will learn about today. Alpha decay Beta decay

Alpha Decay Parent Atom Alpha particle Daughter Isotope

Beta Decay Beta particle Daughter Isotope Parent Atom

The Activity You will be looking at two types of radioactive decay-alpha decay and beta decay. Fill in the table below and then use it to help you figure out what is happening during each type of decay.

Post-Activity Questions What is an alpha particle? Where do you think the electron comes from in beta decay? What do you think is happening in this equation?

Alpha Decay Notes Alpha decay is a form of nuclear decay-radioactivity. An Alpha particle is a Helium atom. During alpha decay: Two protons are lost Two neutrons are lost

Beta Decay Notes During Beta Decay, a neutron inside the nucleus of the atom changed into an electron and a proton. The proton stays inside the nucleus and the electron is emitted.

Check-In What products do you expect if an atom of actinium-227 undergoes alpha decay?

More Practice! Complete the following reactions AND identify whether it is alpha or beta decay: a. b.