People
The Greek philosopher who thought that earth, air, water, and fire were the four elements that made up all matter.
Who is Aristotle?
The basic building blocks of matter which cannot be broken down into anything simpler by chemical reactions.
What are elements?
The smallest unit or particle of an element.
What is an atom?
The chemical formula for water.
What is H2O?
The two MOST common elements in the universe.
What are hydrogen and helium?
The scientist who proposed the idea (in 1803) that elements are made of tiny particles.
Who is John Dalton?
Elements that are shiny, good conductors, and very flexible.
What are metals?
The center of an atom, made up of protons and neutrons and containing most of the atom's mass.
What is a nucleus?
The chemical formula for the oxygen that we breathe.
What is O2?
The most common elements in the ocean.
What are hydrogen and oxygen? (H2O!)
The chart that Dmitri Mendeleev created using cards for each element and ordering them from lightest to heaviest.
What is the Periodic Table of Elements?
Particles with more than one atom joined together.
What are molecules?
The particle in an atom's nucleus that has a positive electric charge.
What is a proton?
The chemical formula for carbon dioxide.
What is CO2?
The three main elements that make up plants, animals, and humans.
What are oxygen, carbon, and hydrogen?
The scientist who came up with the idea of the periodic table of elements in 1869.
Who is Dmitri Mendeleev?
Letters and small numbers that stand for the elements that make up a molecule.
What is a chemical formula?
The particle in an atom's nucleus that has NO electric charge.
What is a neutron?
The tiny numbers in a chemical formula.
What are subscripts?
What is iron?
The scientist who discovered the law of gravity.
Who is Sir Isaac Newton?
Elements that have some properties of metals and some properties of nonmetals.
What are metalloids?
The TINIEST part of an atom that moves in the space outside the nucleus and has a negative electric charge.
What is an electron?
The letters in a chemical formula, which each stand for an element.
What are symbols?
Two very common elements in the earth's atmosphere.
What are nitrogen and oxygen?