Examlex
There are samples of two different isotopes,X and Y.Both contain the same number of radioactive atoms.Sample X has a half-life twice that of Y.How do their decay rates compare?
Hydrogen Atoms
The simplest and most abundant element in the universe, consisting of one proton and one electron.
Water Molecule
the smallest unit of water (H2O), consisting of two hydrogen atoms bonded to one oxygen atom.
Electron Shells
Regions around an atom's nucleus where electrons are likely to be found, each shell having a fixed capacity for electrons.
Magnesium
a lightweight, silvery-white metallic element that is essential for both plant and animal life.
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