Note
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chem 2
Law of Conservation of Mass
In a chemical reaction, the total mass of the substances before and after the reaction stays the same. Nothing is created nor destroyed.
Synthesis
two reactants combine to make a larger or more complex product.
A + B -> AB
Metal + nonmetal -> ionic compound
Oxide: a compound of any element combined with oxygen
metal oxides produce basic oxides
nonmetal oxides produce acidic oxides
Decomposition
one large compound breaks down or decomposes into two or more smaller substances.
AB -> A + B
make this into flashcards pls
Carbonate -> metal oxide + carbon dioxide | CaCO₃ ➔ CaO + CO₂ |
Nitrate -> nitrite + oxygen gas | Mg(NO₃)₂ ➔ Mg(NO₂)₂ + O₂ (g) |
Hydroxide -> metal oxide + water | 2 NaOH (aq) ➔ Na₂O (s) + H₂O (g) |
Peroxide (O2) -> metal oxides + oxygen gas | 2 N₂O₂ ➔ 2 N₂O + O₂ (g) |
Single Displacement
one element displaces another one that's in a compound, producing a new compound and element.
A + BC -> AC + B
A + BC -> BA + C
A lone metal will displace another metal it if it's LOWER than it in the activity series
if the element in the compound is higher, then there is no reaction.
*an element can displace those below it but not above.
Double Displacement
two compounds displace another or trade places,
producing two new compounds.
AB + CD -> AD + CB
AB + CD -> AC + BD
Precipitate Reactions: one product is a solid and the other is aqueous.
Using the solubility table, see the ion combinations that are solid or aqueous in water.
Reactions That Produce a Gas: sulfides, carbonates, and sulfites all react with acids to produce a gas.
sulfides -> H2S(g)
carbonates -> CO2
sulfites -> SO2
Neutralization
an acid and base react to create a neutral water and a salt. (ionic compound)
acid + base -> water + salt
Combustion
*Complete Combustion: oxygen-rich reaction
hydrocarbon + oxygen → carbon dioxide + water vapour + energy
BLUE flame forms during complete combustion
HEAT rather than light is generated
Environmentally:
> produces carbon dioxide (CO₂), a major greenhouse
gas
more CO₂ -> larger greenhouse effect + more climate
change = global warming
Incomplete Combustion: fuel-rich reaction
hydrocarbon + limited oxygen → soot (C), carbon dioxide, carbon monoxide, water vapour, energy
occurs in an enclosed/uncontrolled space with less than ideal conditions
sooty, yellow, and cooler flames.
Environmentally:
> produces harmful pollutants like carbon monoxide (CO) and soot
> more soot = increased respiratory issues and contributes to smog
> CO is a toxic gas that reduces oxygen delivery in the blood