The Structure of an Atom
This tiny particle in the nucleus has a positive charge.
What is a proton?
This is the lightest and first element on the periodic table.
What is hydrogen?
The strong force holds these two types of particles together in the nucleus.
What are protons and neutrons?
Radioactivity is the process where unstable atoms release this.
What is energy or radiation?
Radioactive decay happens at a constant and predictable __________.
What is a rate?
These neutral particles are found in the nucleus alongside protons.
What are neutrons?
The periodic table is organized by increasing numbers of these.
What are protons or the atomic number?
Without the strong force, the nucleus would break apart because of this force between protons.
What is electromagnetic repulsion?
This device is used to detect radiation.
What is a Geiger counter?
This term describes how long it takes for half of a radioactive substance to decay.
What is a half-life?
These negatively charged particles orbit the nucleus of an atom.
What are electrons?
These are the vertical columns on the periodic table.
What are groups or families?
This fundamental force is the strongest of all four forces in nature.
What is the strong nuclear force?
This type of radiation can be stopped by just a sheet of paper.
What is alpha radiation?
Scientists use this method to determine the age of ancient fossils or rocks.
What is radioactive dating?
This part of the atom contains most of its mass.
What is the nucleus?
This element is a metal, is liquid at room temperature, and is toxic.
What is mercury?
The strong force works only over this kind of distance.
What is a very short or subatomic distance?
The time it takes for half of a radioactive substance to decay is called this.
What is a half-life?
This radioactive element is commonly used to date fossils up to about 50,000 years old.
What is carbon-14?
The number of these in an atom determines which element it is.
What are protons?
Elements on the far right of the periodic table that don’t usually react with other elements belong to this group.
What are the noble gases?
The particles inside protons and neutrons that the strong force holds together are called these.
What are quarks?
These particles are ejected from an atom during beta decay.
What are electrons (or beta particles)?
If a sample starts with 100 grams of a radioactive isotope, how much would remain after 2 half-lives?
What is 25 grams?