Unit 7 - Isotopes + Radioactivity

Isotopes definition

isotopes are Atoms of the same element with the same atomic number but a different atomic mass due to a change in the number of neutrons

Examples of isotopes

protium, deuterium, tritium

notation

element - atomic mass

protium

hydrogen-1
used to make ammonia with nitrogen and is used to turn unsaturated/liquid fats into solid fats for food and soaps

deuterium

hydrogen-2
used to produce hydrogen bombs

tritium

hydrogen-3
used in nuclear fusion reactions and can be an artificial radioactive tracer

relative atomic mass

(% of isotope x mass) + (% of isotope x mass) / 100 =

stable nuclei

balanced number of protons and neutrons. naturally stable nuclei are located in the lighter section of the periodic table. all nuclei with proton numbers under 83 are naturally stable

unstable nuceli

unbalanced number of protons and neutrons. generally heavy because of excess protons and neutrons therefore causing them to decay and emit particles. all nuclei with proton numbers over 83 are unstable and reactive

decay series

A sequence of decay where a radioactive element breaks down into different elements until reaching stability.

parent isotope

unstable, radioactive atom that undergoes radioactive decay to form a more stable product

daughter isotope

isotope formed from the decay of the parent isotope

half-life

The half-life of a radioactive isotope is the time taken for half of the unstable nuclei in a sample to decay.

transuranic elements

Transuranic elements are radioactive elements with atomic numbers greater than 92, meaning they occur after uranium in the periodic table.

types of radioactivity

alpha, beta, gamma

alpha

form of decay where 2 protons and 2 neutrons are emitted. the alpha particles are like a helium nucleus as it contains 2 neutrons and 2 protons

-4 from atomic mass, -2 from atomic number

beta

form of decay by which a neutron changes into a proton, emitting an electron. beta particles are like an electron that increases the atomic number of the isotope. the atomic mass stays the same

same atomic mass, +1 atomic number

gamma

form of decay wehre gamma rays are emitted usually after alpha or beta decay. usually protons or electromagnetic energy released from isotopes
atomic mass and atomic number stays the same

geiger counter

Device used to detect for radioactive emissions in industries where radioactive elements are used. It is mostly used to detect beta and gamma radiation. It works by using inert gases that becomes unnaturally conductive of electricity when impacted by high-energy particles or radiation

fusion reaction

nuclear reaction in which 2 light atomic nuclei combine to form a heavier nucleus releasing a large amount of energy because some mass is converted into energy. It occurs at high temperature and pressure int eh core.

deduce whether the phrase we are all stardust is true

It is mostly true scientifically because many of the elements that make up the eartha nd human bodies were created in stars through fusion and distributed by supernova explosions.