A way to show the elements in a chemical and how many atoms of each there are in it
100
What are the components of a chemical reaction?
products and reactants
100
What is a chemical change?
A permanent change that chemically changes the material into a new substance
100
What does it mean to balance an equation?
There are the same number of atoms on each side of the equation
200
What does a coefficient tell us?
The coefficient tells us how many molecules there are in a chemical equation.
200
2H2 + O2 --->2H2O
What are the reactants in this equation?
2H2 + O2
200
What is a physical change?
A change that is reversible and does not change the chemical composition of the material.
200
What law is represented by a balanced equation?
The Law of Conservation of Matter
300
What is the coefficient in 3H2O?
3
300
What was evidence of a chemical reaction when we mixed hydrogen peroxide and yeast?
It produced heat (exothermic) and bubbled
300
Tearing paper is an type of _____________ change.
physical
300
Bubbles in a chemical reaction are a sign of....
gas being produced by the reaction
400
What does a subscript tell us?
The number of each atom of an element.
400
2H2 + O2 --->2H2O
What is/are the products in this equation?
2H2O
400
Rusting or oxidation is an example of a ____________ change.
chemical
400
If 15 grams of baking sodium is combined with 5 grams of vinegar the resulting reaction of solid, liquid, and gas should have a mass of _________ grams.
20 grams
500
What is the subscript in 3H2O
2
500
2H2 + O2 --->2H2O
Is this equation balanced?
yes
500
Name three signs that a chemical reaction has occurred.
Any 3...
bubbling
temperature change
color change
odor change
light produced
precipitate formed