Particles Flashcards
Overall the atom is ____
neutral
What is an isotope
An isotope of an element has the same number of protons but a different number of neutrons
are all isotopes stable
No, carbon 12 is stable while carbon 14 is unstable
What are the 3 types of nuclear radiation
Alpha, beta, gamma
When does nuclear radiation occur
An unstable nuclei can emmit radiation to become stable again.
Describe Alpha radiation
Alpha radiation takes the form of a helium nuclei with an atomic number of 2 and atomic mass of 4 (2 protons and 2 neutrons) This means it has a +2 charge. They are given the symbol He. α.
Describe Beta radiation
Beta radiation takes the form of fast moving electrons. These have an atomic number of -1 and atomic mass of 0 and are given the chemical symbol e. They have a charge of -1. β.
Describe gamma radiation
Gamma radiation takes the form of a high frequency EM wave. It has a charge of 0. γ
When nuclei decay what happens to the mass and atomic number
They are conserved. THis means the to value is the same before and after the decay.
When gamma is emmitted what happens to the decay equation
Only energy is emmited and the daughter product is the same as the parent.
Define nuclear fission
Nuclear fission is the splitting of a heavy nucleus into 2 nuclei of smaller mass number, with the release of neutrons and energy.
What 2 ways can nuclear fission occur in
Spontaneously or by bombardment of neutrons (induced fission)
What does Einsteins equation show
mass is equivalent to energy
State Einsteins equation
E=mc^2
E = energy in Joules(J)
m = mass in kg
c = speed of light
Why is energy released in a fission reaction
The mass after a fission reaction is slightly less than the mass before (although the total mass number doesn’t change)
This “lost mass” is converted to energy (according to e = mc^2), and released as kinetic energy of the fission products.
Define nuclear fusion
Nuclear fusion is when two light nuclei combine to form a larger nucleus
Is mass conserved in fusion
No in nuclear fusion mass is “lost” in the process which is converted to energy and released as kinetic energy of the fusion products
What temperature is required to fuse two nuclei together
about 100,000,000 K
How do stars achieves fusion
Stars achieve nuclear fusion with a core at only 15,000,000 K because the heat energy is combined with enormous pressure. This process lead to four million tonnes of mass being lost every second and released as energy.
How do we measure order of magnitude
Difference in order of magnitude = difference in power
What is the standard model
The standard model is a model of fundamental particles and their interactions.
What is a fundamental particle
A fundamental particle is a particle that cannot be divided into smaller particles.
What are the two types of fundamental particles
Matter particles and Force mediating particles
What are fermions
Fermions are the matter particles that include all quarks and leptons.