Chapter 4 Flashcards
Beta decay turns a neutron into a ________ & it ejects an electron or vise versa (negative ebeta decay gains an electron for the daughter atom & mass number stays the same)( when theMCAT mention beta decay without context it referring to negative beta decay)
proton
Positive beta decay (position emission)
When the daughter atom gains a proton
Electron capture
Reduced the neutrons so it gains a proton
Gamma decay
Brings an excited nucleus to a lower energy state after an alpha or beta decay (doesn’t change anything)
Half life
Is the time it takes for one half of some sample of the substance to decay (the shorter the half life then the faster the decay)
delta m (mass defect) which is also the difference of the nuclear binding energy, what is its formula?
delta m = (total mass of separate nucleons) - (mass od nucleus)
What is the formula for the nuclear binding energy (Eb)
E(b)= mc^2( c is the speed of light) (or E(b) in eV = m(in amu) x 931.5 MeV)
What is the equation related to the emission spectrum
E (photon) = h(c/wave-length) (h is plank constant 6.63 x 10^-34 & c is the speed of light)
What does the letter Z represent?
It’s the atomic number (the number of protons on an atom)
What does the letter A represent?
Its the mass number (A= Z + N (N is neutrons))
Isotopes
When two atoms of the same element differ in their number of neutrons (same atomic number but different mass number)
The atomic weight of an element is the weight _______________ of its mass
Average
Unstable nuclei are radioactive & undergo ______________ to make them more stable
Radioactive decay
What are the different types of radioactive decay?
Alpha, negative beta, positive beta, gamma
Alpha decay does what?
Reduce the atomic mass by 4 & the atomic number by 2 (reduced protons by 2)
All types of beta decay do what?
Transfer a neutron into a proton
Negative beta decay (most common)
Increases the atomic number by 1 (protons increase by 1, & should assume negative decay unless stated otherwise)
Positive decay (positron emission)
Converts a proton into a neutron, atomic number decreases by 1 (lose a proton)
Electron capture reduce atomic number (proton) by __
1
Gamma decay relax an excited state element & doesn’t ___________ anything
Change
___________ is the time it takes for 1/2 of the sample to decay
Half-life
