Which of the following has the same number of neutrons as ⁴⁰₁₈Ar?
Neutrons in Ar = 22. ⁴¹₁₉K also has 22 neutrons.
Ref: NCERT Class 11 Chemistry > Chapter 2: Structure of Atom > Topic: Discovery of Subatomic Particles - Electron Proton Neutron
#isotope
3 public questions tagged with this topic.
Filter questions
Which isotope is suitable for solid scintillation?
Solid scintillation uses thallium-activated sodium iodide crystals that produce light flashes when interacting with penetrating photons. Tritium, carbon-14, and sulfur-35 emit low-energy beta particles unable to penetrate crystal housing and efficiently interact, better suited for liquid scintillation where sample is intimately mixed. Cobalt-60 emits strong gamma rays of 1.17 and 1.33 MeV that penetrate crystal and generate ample scintillation photons detectable by photomultiplier. Therefore strong gamma emitters like cobalt-60 and sodium-24 are preferred isotopes for calibration and measurement with solid scintillation systems.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.
Which isotope has a half-life of 5730 years?
Carbon-14 is formed in upper atmosphere by neutron interaction with nitrogen and incorporated through photosynthesis into living matter. Its half-life of approximately 5730 years is long enough that measurable amounts remain over millennia yet short enough to show measurable decay difference. Dead organisms stop carbon exchange, and remaining carbon-14 decays, enabling estimation of age up to 50000 years. Short-lived isotopes like phosphorus-32 survive days and sulfur-35 weeks, useless for archaeological timescales. Therefore 5730 year half-life uniquely identifies carbon-14 among common tracers.
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.