1. (Chemical Equations & Chemical Reactions)
Conservation of Mass
(Chemical Equations & Chemical Reactions)
HS-PS1-7 Level 1

2. Chemical Reaction →
when the bonds between atoms of a substance are broken and the atoms rearrange and form new bonds to make substances.

3. How do you know when a chemical reaction occurs? What is your evidence?
Temperature change
Color Change
(not color intensity)
Light

4. Appearance of a solid
(precipitate)
Gas formation
Formation of

5. uses symbols and formulas to show what happens in a chemical reaction
Chemical Equation  →
uses symbols and formulas to show what happens in a chemical reaction
H2O(l) + NaHCO3(s) → NaOH(aq) + CO2(g) + H2O(l)

6. H2O(l) + NaHCO3(s) → NaOH(aq) + CO2(g) + H2O(l)
Reading a Chemical Equation….
** the arrow is read as “yields” or “produces”**
H2O(l) + NaHCO3(s) → NaOH(aq) + CO2(g) + H2O(l)
water plus sodium bicarbonate yields sodium hydroxide plus carbon dioxide plus water

7. Product(s) Reactant(s) Parts of a Chemical Equation
H2O(l) + NaHCO3(s) → NaOH(aq) + CO2(g) + H2O(l)
Product(s)
Reactant(s)
*what is used in a reaction
*always BEFORE the arrow
*what is produced/made during a reaction
* Always AFTER the arrow

8. phase notations l = liquid
H2O(l) + NaHCO3(s) → NaOH(aq) + CO2(g) + H2O(l)
phase notations
l = liquid
s = solid
aq = aqueous (dissolved in water)
g = gas

9. coefficient 2H2(g) + O2(g) → 2H2O(l)
* number before the formula of a compound or single element
* how many you have of a compound
* no number = 1
coefficient

10. closed system = sealed environment
Conservation of Mass
In a closed system, the total mass of the products from a chemical reaction will equal the total mass of the reactants;
mass is CONSERVED
closed system = sealed environment