Reaction Library
Curated balanced equations with types, conditions, and observable changes. Filter by reaction type or search the equation.
Formation of water
2 H2 + O2 -> 2 H2O
2 H2 + O2 -> 2 H2O
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Electrolysis of water
2 H2O -> 2 H2 + O2
2 H2O -> 2 H2 + O2
Conditions: electrolysis
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Thermal decomposition of calcium carbonate
CaCO3 -> CaO + CO2
CaCO3 -> CaO + CO2
Conditions: heat ~840 °C
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Single displacement zinc and acid
Zn + 2 HCl -> ZnCl2 + H2
Zn + 2 HCl -> ZnCl2 + H2
Conditions: room temp
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Precipitation of silver chloride
AgNO3 + NaCl -> AgCl + NaNO3
AgNO3 + NaCl -> AgCl + NaNO3
Conditions: aqueous
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Neutralization of HCl and NaOH
HCl + NaOH -> NaCl + H2O
HCl + NaOH -> NaCl + H2O
Conditions: aqueous
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Combustion of methane
CH4 + 2 O2 -> CO2 + 2 H2O
CH4 + 2 O2 -> CO2 + 2 H2O
Conditions: flame
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Combustion of ethane
2 C2H6 + 7 O2 -> 4 CO2 + 6 H2O
2 C2H6 + 7 O2 -> 4 CO2 + 6 H2O
Conditions: flame
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Combustion of ethanol
C2H6O + 3 O2 -> 2 CO2 + 3 H2O
C2H6O + 3 O2 -> 2 CO2 + 3 H2O
Conditions: flame
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Combustion of benzene
2 C6H6 + 15 O2 -> 12 CO2 + 6 H2O
2 C6H6 + 15 O2 -> 12 CO2 + 6 H2O
Conditions: flame
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Haber-Bosch synthesis
N2 + 3 H2 <-> 2 NH3
N2 + 3 H2 <-> 2 NH3
Conditions: high pressure, catalyst Fe, 400-500 °C
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Decomposition of hydrogen peroxide
2 H2O2 -> 2 H2O + O2
2 H2O2 -> 2 H2O + O2
Conditions: catalyst MnO2 or KI
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Acid–carbonate gas evolution
NaHCO3 + HCl -> NaCl + H2O + CO2
NaHCO3 + HCl -> NaCl + H2O + CO2
Conditions: aqueous
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Redox single displacement Zn/Cu
Zn + CuSO4 -> ZnSO4 + Cu
Zn + CuSO4 -> ZnSO4 + Cu
Conditions: aqueous
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Thermite reaction
Fe2O3 + 2 Al -> Al2O3 + 2 Fe
Fe2O3 + 2 Al -> Al2O3 + 2 Fe
Conditions: high temp
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Photosynthesis
6 CO2 + 6 H2O -> C6H12O6 + 6 O2
6 CO2 + 6 H2O -> C6H12O6 + 6 O2
Conditions: light chlorophyll
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Esterification
CH3COOH + C2H5OH -> CH3COOC2H5 + H2O
CH3COOH + C2H5OH -> CH3COOC2H5 + H2O
Conditions: acid catalyst
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Precipitation of barium sulfate
BaCl2 + Na2SO4 -> BaSO4 + 2 NaCl
BaCl2 + Na2SO4 -> BaSO4 + 2 NaCl
Conditions: aqueous
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Thermal decomposition of sodium bicarbonate
2 NaHCO3 -> Na2CO3 + H2O + CO2
2 NaHCO3 -> Na2CO3 + H2O + CO2
Conditions: heat
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Ethanol fermentation
C6H12O6 -> 2 C2H6O + 2 CO2
C6H12O6 -> 2 C2H6O + 2 CO2
Conditions: yeast anaerobic
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Dinitrogen tetroxide equilibrium
2 NO2 <-> N2O4
2 NO2 <-> N2O4
Conditions: temperature dependent
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Ammonia and HCl
NH3 + HCl -> NH4Cl
NH3 + HCl -> NH4Cl
Conditions: gas/ aqueous
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Ostwald process — nitric acid formation
NH3 + 2 O2 -> HNO3 + H2O
NH3 + 2 O2 -> HNO3 + H2O
Conditions: Pt/Rh catalyst, 900 °C
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Combustion of acetone
C3H6O + 4 O2 -> 3 CO2 + 3 H2O
C3H6O + 4 O2 -> 3 CO2 + 3 H2O
Conditions: flame
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Urea synthesis (Bosch-Meiser)
2 NH3 + CO2 -> CH4N2O + H2O
2 NH3 + CO2 -> CH4N2O + H2O
Conditions: high pressure, 180–210 °C
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Thermal decomposition of sodium nitrate
2 NaNO3 -> 2 NaNO2 + O2
2 NaNO3 -> 2 NaNO2 + O2
Conditions: heat ~380 °C
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Precipitation of calcium sulfate
CaCl2 + Na2SO4 -> CaSO4 + 2 NaCl
CaCl2 + Na2SO4 -> CaSO4 + 2 NaCl
Conditions: aqueous
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Combustion of carbon
C + O2 -> CO2
C + O2 -> CO2
Conditions: flame
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →Thermal decomposition of potassium nitrate
2 KNO3 -> 2 KNO2 + O2
2 KNO3 -> 2 KNO2 + O2
Conditions: heat ~400 °C
Observable changes as per reaction type — gas evolution, precipitate, color change, or temperature change.
View reaction →How these equations are checked
Every reaction is verified by the shared equation balancer (exact rational null-space) to ensure atom and charge balance where applicable. Equations that require explicit water/H⁺/OH⁻ for redox are stored as full balanced molecular equations. Conditions and catalysts are documented separately from stoichiometry.
Lesson: Balancing equations →