This energy from this type of reaction is often released through heat.
Exothermic
What is a compound?
When one or more atoms combine together, they are called compounds
One of the three types of subatomic particles. [Has a positive charge]
Protons
The new substance formed in a chemical reaction.
Product
The three groups of elements on the periodic table.
Metals, metalloids, and nonmetals
Chemical reaction that absorbs energy and feels cold
Endothermic Reactions
The element with 21 protons
Scandium
All matter is composed of...
Atoms
A change in matter that does not result in a new substance.
Physical change
Tell 2 properties of metals
Shiny, malleable, conductive, ductile
Fire is a _________ reaction
Exothermic
What are the reactants in this reaction?
Cr + O2 → Cr2O3
Cr and O2
The center of an atom
Nucleus
This law states that matter is never created nor destroyed.
The Law of Conservation of Mass
Tell 2 properties of nonmetals
Dull, brittle, poor conductors
What elements and how many atoms: 3Na2OH3
Na = Sodium, 6
O = Oxygen, 3
H = Hydrogen, 9
What is the atomic number?
79
This type of subatomic particle has a negative charge
Electron
If a chemical change has happened, a ___ happened as well.
Chemical reaction
The elements in last column of the periodic table are called
Nobel Gases
Balance the equation:
Cr + O2 → Cr2O3
4Cr + 3O2 → 2Cr2O3
Look up element #73 and tell 2 of its properties
Shiny, ductile, malleable, good conductor
This type of particle does not have a charge
Neutron
The 4 main signs of a chemical reaction
Solid formation, gas formation, color change, temperature change
The elements in a column all share similar _______
properties