Atoms
Atoms.
What makes up everything around us?
When one substance reacts with another to produce a new substance.
What are chemical reactions?
A chart of systematically grouped elements.
What is the periodic table?
An equation used to model a chemical reaction.
What is a chemical equation?
Protons, neutrons, and electrons
What makes up atoms?
Reactions that absorb heat.
What are endothermic reactions?
By atomic number and similar properties.
How is the periodic table grouped?
Electron cloud.
Where do electrons go when they go around the nucleus of an atom?
Protons are positive, electrons have a negative charge, and neutrons have no charges at all.
What are the charges of protons, electrons, and neutrons?
Reactions that release heat.
What are exothermic reactions?
Dmitri Mendeleev.
Who created the first version of the Periodic Table?
The average mass of the element.
What is a mass number?
Electrons
Which particle weighs almost nothing?
They speed up a reaction without changing itself.
What is a catalyst?
Metals, metalloids, and nonmetals.
In what three categories are the elements grouped in?
One of the substances that react with the other.
John Dalton
Who was the earliest scientist who contributed to the modern atomic theory?
They slow down a reaction.
What is an inhibitor?
Henry Moseley.
Who edited the periodic table after Mendeleev?
A group of elements with some properties of metals and some properties of nonmetals.
What is a metalloid?