Identifying Reactions/Predicting Products
What kind of reaction is being displayed here? How do you know?
Na + Cl2 →
Synthesis (E + E)
Balance the following reaction: Li + Br2 → LiBr
2Li + Br2 → 2LiBr
Identify whether the following molecule is soluble or insoluble: MgCO3
Insoluble
Draw the resulting beaker diagram when salt is dissolved in water.
Beaker diagram should contain H2O (l) and Na+ Cl- ions.
Name one indicator that a chemical change is occurring.
New odor, unexpected color change, production of heat AND light, formation of a precipitate, production of a gas.
Which reaction type starts with a sole compound in the reactants? Additionally, what does this reaction entail (making, breaking, or rearranging bonds)?
Decomposition, which involves breaking bonds.
Balance the following equation: CaCl2 + Na3PO4 → Ca3(PO4)2 + NaCl
3CaCl2 + 2Na3PO4 → Ca3(PO4)2 + 6NaCl
Identify whether the following molecule is soluble or insoluble: LiNO3
Soluble
Draw a beaker diagram containing Mg2(PO4)3.
This molecule is insoluble so it should just be written as Mg2(PO4)3 (s) in the beaker.
Name one indicator that a physical change is occurring.
Dissolvation, natural/expected phase change, change in size/shape of matter
Identify the following reaction type and predict the products:
CH4 + O2 →
Combustion. CO2 + H2O are the products.
Balance the following equation: Fe2O3(s) + C(s) → Fe(s) + CO2(g)
2Fe2O3(s) + 3C(s) → 4Fe(s) + 3CO2(g)
Identify whether the following molecule is soluble or insoluble: lead (II) chloride
Insoluble.
Draw a beaker diagram containing Li2(CrO4).
This molecule is soluble so the beaker diagram should contain two Li+ ions and one CrO42- ion.
Is water freezing a physical or a chemical change? How do you know?
Water freezing is a physical change because it's an expected phase change.
What's wrong with this reaction? Explain and make it better!
Fe2O3 → Fe + O
HOFBrINCl! Fe2O3 -> Fe + O2
The following reaction is balanced incorrectly. Fix it!
2Na + 2H2O → 2NaOH + H2
Give me an example of a soluble molecule that contains something that's typically insoluble.
Multiple correct answers! The answer should contain a generally insoluble species that's paired with an exception.
Draw the reactant and product beaker diagrams for the following reaction:
MgCl2(aq) + Na2SO4(aq)→ MgSO4 + 2NaCl
Reactant 1 beaker: Mg2+, Cl-, Cl-
Reactant 2 beaker: Na+, Na+, SO42-
Product beaker: Mg2+, SO42-, Na+, Na+, Cl-, Cl-
In the lab, I mix baking soda and vinegar in a flask and cover the flask with a balloon. The balloon then starts to fill up. Is this a physical or a chemical change? How do you know?
This is a chemical change because gas is being produced.
Write the entire reaction in words:
HgO →
Mercury (II) oxide breaks down into mercury and oxygen.
Balance the following equation: Al2(CO3)3 + H3PO4 → AlPO4 + CO2 + H2O
Al2(CO3)3 + 2H3PO4 → 2AlPO4 + 3CO2 +3 H2O
Assign states to the following reaction: FeCl3 + NaOH → Fe(OH)3 + NaCl
(aq), (aq) → (s), (aq)
Write a balanced reaction with states for the following reaction and draw both the reactant and product beaker diagrams:
Solutions of copper (II) sulfate and sodium hydroxide react in a double displacement reaction.
CuSO4 (aq) + 2NaOH (aq) -> Cu(OH)2 (s) + Na2SO4 (aq)
Reactant beaker 1: Cu2+ and SO42-
Reactant beaker 2: Na+ Na+ OH- OH-
Product beaker: Cu(OH)2 (s) and Na+ Na+ SO42-
Is burning a candle and watching the wax melt a physical or chemical change? How do you know?
Both! The burning of the candle is a chemical change because ash is produced. The wax melting is a physical change because the wax is just changing states.