This is an atom that has gained or lost electrons.
What is an ion?
The atomic number refers to the number of these in an atom.
What are protons?
Unstable thorium-230 breaks down into the 226 isotope of this Curie-ous element.
What is radium?
Nuclear decay in some atoms can cause the emission of this in the form of alpha & beta particles or gamma rays.
What is radiation?
With the same mass & magnitude of charge, an antiparticle of an electron is called this word.
What is a positron?
Bananas have a tiny amount of radioactivity due to this element, which can emit .01 millirems of radiation.
What is potassium?
Isotopes are 2 forms of an element with the same number of protons but different numbers of these particles
What are neutrons?
From the Latin for "fall off", it's the process by which radioactive radium emits radiation.
What is decay?
DAILY DOUBLE
Objects with different charges do this when they come close to each other.
What is attract?
The standard model of particle physics accounts for 3 of the 4 fundamental forces, skipping this one, important in daily life.
What is gravity?
In 1960 the wavelength of light from krypton-86 was used to define this measurement, also 39.37"
What is a meter?
Radiation laden radon-222 is a by-product of mining this element that's named for a planet (and Greek god of the sky).
What is uranium?
In 1913 Niels Bohr theorized that these move in fixed orbits around an atom's nucleus.
What are electrons?
Using mass spectrometry, neon was the first element shown to exist in more than one of these stable variations.
What is an isotope?
As in planetary sequence, neptunium-239 emits a beta particle & becomes isotope 239 of this element.
What is plutonium?
First things first--this particle can become the nucleus of a helium atom by capturing 2 electrons
What is an alpha particle?
DAILY DOUBLE
These 2 types of particles in an atom's nucleus are bound together by the "strong force".
What are protons and neutrons?
An atom may become more stable by releasing this Greek letter particle, identical to a helium atom nucleus.
What is an alpha particle?
The hydrogen isotope called this was discovered in 1932, 2 years before tritium.
What is deuterium?