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all substance are made of
what are molecules a collection of atoms?
How scientists represent chemical reactions
What are chemical equations?
This is what happens in a chemical reaction
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?
Some chemical reactions require this.
What is a catalyst?
Who is Antoine Lavoisier?
All chemical reactions involve this.
What is energy?
The law of conservation of mass
When atoms cannot be created or destroyed only rearranged.
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?
The most noticeable physical changes in a chemical reaction.
What are odor and color?
Most chemical reactions can be described as this.
What is exothermic and 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.
What is the equal number of atoms.
Symbol for hydrogen
What is H
Symbol for lithium
What is Li?
Symbol for potassium
What is K
An element or compound
What is chemical?
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?