1.2 Atomic Structure and Mass Flashcards
What are isotopes?
atoms w same no. of protons but diff no. of neutrons
Do neutrons have the same chem properties but diff physical properties?
Yes
Why are elements above 82 unstable?
Too many protons + neutrons
What are stable isotopes?
atoms w a stable nucleus, not radioactive
Do stable isotopes have a half-life
No, or very long
What are unstable isotopes?
too many or too few neutrons in nucleus, radioactive
Is the half-life of radioisotopes long or short?
short
What are radioisotopes used for?
DNA analysis, MRI, fossil dating
Do radioisotopes decay to form stable isotopes
Yes
What is relative mass?
The standard to which all atoms compared to C-12
What is the formula for relative atomic mass?
AR=(relative atomic mass 1 x % abundance) + (relative atomic mass 2 x % abundance) /100
What is the band of stability?
a plot of the no. of neutrons vs protons, reveals that stable isotopes fall into a narrow band
Are radioisotopes with a short half life highly radioactive or not radioactive?
Highly radioactive
What is iodine-131 used in ?
thyroid cancer therapies
What is a spectrometer?
Lab instrument used to detect isotopes of an element and to determine both relative mass and abundance of each isotope
