Reactions
Determine the reaction:
Perfume evaporating on your skin
physical change
Determine the equation:
all species in reaction
balanced molecular equation
2.5 mol of CaO reacts with 3.0 mol of SO2 and 2.0 mol of O2 to produce CaSO4. The balanced equation:
2CaO + 2SO2 + O2 ---> 2CaSO4
Determine the limiting reagent.
CaO
As ---> H3AsO4 + AsH3
find the balanced redox reaction (acidic)
12H2O + 8As ---> 3H3AsO4 + 5AsH3
Determine the type of chemical reaction:
when a covalent substance containing carbon and hydrogen (and sometimes oxygen) is ignited, it reacts with oxygen in the atmosphere and the result is ALWAYS CO2 and H2O. If other elements are present, they may oxidize and create various gasses. It is not always possible to predict what non-carbon, non-hydrogen compounds will form, but Carbon combustion will ALWAYS lead to CO2, and Hydrogen to H2O.
Hydrocarbon Combustion
Determine the reaction:
Mixing sugar in water
physical change
ions in aq solution as separate particles
complete ionic equation
A sample of sodium bicarbonate (NaHCO3) is known to contain some impurities. It is found that Na makes up 18.00% of the entire mass of the sample. All of the Na comes from the NaHCO3. Find the mass percent of NaHCO3 in the sample.
65.78%
H3AsO4 + Zn + HNO3 --> AsH3 + Zn(NO3)2
Balance the redox reaction (acidic)
8HNO3 + H3AsO4 + 4Zn ---> AsH3 + 4Zn(NO3)2 + 4H2O
Determine the type of chemical reaction:
a reaction when an acid (H+) reacts with a base (OH-) to form a water and salt.
acid base reaction
Determine the reaction:
melting copper metal
Physical change
Determine the equation:
do not include spectator ions
Net ionic equation
A mixture of potassium chloride and potassium bromide weighing 3.595 g is heated with chlorine gas, which converts the mixture completely to potassium chloride. The total mass of the KCl after the reaction is 3.129 g. What percent of the original mixture is KBr?
34.71%
Co(OH)2(s) + SO32¯(aq) ---> SO42¯(aq) + Co(s)
Balance the redox reaction (basic)
SO32¯(aq) + Co(OH)2(s) ---> Co(s) + SO42¯(aq) + H2O
Determine the type of chemical reaction
when 2 aq solutions mix, sometimes a new cation/anion paring can create an insoluble salt called a precipitate.
precipitation
Determine the reaction:
hydrofluoric acid attacks glass
chemical reaction
Determine the equation:
2Na+(aq) + 2OH-(aq) + Cu2+(aq) + SO42-(aq) → 2Na+(aq) + SO4 2-(aq) + Cu(OH)2(s)
complete ionic equation
Solid calcium carbonate, CaCO3, is able to remove sulphur dioxide from waste gases by this reaction (balanced as written):
CaCO3 + SO2 + other reactants ---> CaSO3 + other products
In a particular experiment, 255 g of CaCO3 was exposed to 135 g of SO2 in the presence of an excess amount of the other chemicals required for the reaction.
(a) What is the theoretical yield of CaSO3?
253 g CaSO3
Au + NaCN + O2 + H2O ---> NaAu(CN)2 + NaOH
Balance the redox reaction (Basic)
4Au + 8CN¯ + 2H2O + O2 ---> 4Au(CN)2¯ + 4OH¯
Determine the type of chemical reaction:
When elements or compounds are combined to form a single more complex compound.
synthesis reaction
Determine the reaction:
mixing baking soda and vinegar together
Chemical change
Determine the equation:
2OH-(aq) + Cu2+(aq) → Cu(OH)2(s)
net ionic equation
An ore of barium contains BaCO3. A 1.495 g sample of the ore was treated with HCl to dissolve the BaCO3. The resulting solution was filtered to remove insoluble material and then treated with H2SO4 to precipitate BaSO4. The precipitate was filtered, dried, and found to weigh 1.152 g. What is the percentage by mass of barium in the original sample?
45.34%
Se + Cr(OH)3 ---> Cr + SeO32¯
Balance the redox reaction (Basic)
6OH¯ + 3Se + 4Cr(OH)3 ---> 4Cr + 3SeO32¯ + 9H2O
Determine the type of chemical reaction:
the opposite of synthesis. A reaction where a single compound is split into two or more elements of simple compounds. Usually in the presence of heat.
decomposition