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All matter is made of
Atoms
How scientists represent chemical reactions
What are chemical equations?
What happens when bonds between atoms in a reactants are broken and the atoms of a difference substance are rearranged and then a new bond is formed?
a chemical reaction
Some chemical reactions require this.
What is a catalyst?
Who is Antoine Lavoisier?
What happens to atoms during a chemical reaction?
They are rearranged into new substances.
When atoms cannot be created or destroyed only rearranged.
The law of conservation of mass
One way to look at a chemical change.
What are physical changes?
The left side of the arrow in a chemical equation.
What is a reactant?
The right side of a chemical equation
What is a product?
Name two signs that a chemical reactions has occurs
Presence of bubbles
Change in color
Change in temperature
Formation of a precipitate
Most chemical reactions can be described as this based on the change in temperature
exothermic or endothermic?
Scientists represent elements this way.
what is a symbol.
Chemical equations have to be this way.
What is balanced?
The number in frond of the molecule in a chemical equation.
What is a coefficient?
The small number on a molecule in a chemical equation.
What is a subscript?
Chemical reactions produce this
What is a new substance?
Balanced chemical equations have to have this on both sides.
equal number of atoms.
Symbol for hydrogen
What is H
Symbol for lithium
What is Li?
Symbol for potassium
What is K
How do we represent a chemical compound?
Formula
chemical reaction that gives off heat
What is exothermic?
chemical reaction that absorbs heat energy
What is endothermic
two or more atoms joined together
What is a molecule?