Unit 6 Flashcards
List the 7 signs that a chemical reaction has taken place.
- Temperature change
- Gas evolved (given off)
- Dramatic Color Change
- Formation of a precipitate
- New odor
- Light/sparks
- Sound
What does the symbol (l) mean?
liquid
What does the symbol (aq) mean?
aqueous; substance has been dissolved in water
What does the symbol (ppt) mean?
precipitate
What does the symbol (g) mean?
gas
What does the symbol (s) mean?
solid
What does the symbol → mean?
yields/produces
What does the symbol —△→ mean?
reaction requires heat
What does the symbol —Pt→ mean?
reaction requires a catalyst, in this case platinum
What does the symbol —ele→ mean?
reaction requires electricity
What kind of reaction is this?:
A + B → AB
Synthesis
What kind of reaction is this?:
AB → A + B
Decomposition
What kind of reaction is this?:
A + BC → AC + B
Single Replacement
What kind of reaction is this?:
AB + CD → AD + CB
Double Replacement
What kind of reaction is this?:
CH₄ + O₂ —△→ CO₂ + H₂O
Combustion
What kind of reaction is this?:
HX(acid) + Z(OH)(base) → a salt + H₂O
Neutralization
What kind of element cannot occur alone? It occurs as a pair. There are 7.
Diatomic Element
H₂, N₂, O₂, F₂, Cl₂, Br₂, I₂
What does a decomposition of a metal carbonate produce?
ex. Li₂(CO₃) —△→
It produces a metal oxide and CO₂.
Li₂O +CO₂
What does a decomposition of a metal hydroxide produce?
ex. Ca(OH)₂ —△→
It produces a metal oxide and water—except Group 1.
CaO + H₂O
What does a decomposition of a metal chlorate produce?
ex. 2Li(ClO₃) —△→
It produces a metal chloride and oxygen gas.
2LiCl + 3O₂
What shows just the species that are NOT aqueous ions as products. This is the precipitate.
The net ionic equation.
What are the aqueous ions called? Those ions that do not come together to form a precipitate. (must look at solubility rules for this)
The spectator ions.
What must a combustion reaction always have?
O₂ —△→ CO₂ + H₂O
What must a neutralization reaction always have?
an acid + a base → a salt + water
In what instance do you have a precipitate for a product?
You have a precipitate in the product when you have a double replacement reaction with two aqueous substances.
In part 1a. of the lab, what was added to the copper II sulfate? What was the resulting color of the metal?
Zinc was added to the copper II sulfate. It went from silver to reddish brown.
In part 1b. of the lab, what was added to the aqueous silver nitrate? What was the resulting color of the metal?
Copper was added to the silver nitrate. It went from reddish brown to silver.
In part 2a. of the lab, what were the beginning and ending colors of the ammonium dichromate after it was heated?
The ammonium dichromate went from bright orange to dark forest green.
In part 2b. of the lab, what happened to the C₁₂H₂₂O₁₁ (sugar) when it was heated?
The sugar turned from white to black and brown. It also had some smoke and a new odor.
In part 3a. of the lab, what happened when sodium hydroxide was added to ferric chloride?
The ferric chloride went from orange to dark brown.
In part 3b. of the lab, what happened when ammonium hydroxide was added to copper II sulfate?
The copper II sulfate went from light blue to a very dark blue.
In part 3c. of the lab, what happened when potassium iodide was added to lead II nitrate?
The lead II nitrate went from cloudy-clear to a bright solid-colored yellow.
