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Add a few drops of aqueous potassium iodide to a solution containing an unknown agent.
If an oxidizing agent is present in the solution, aqueous potassium iodide will turn from colorless to brown.
In the presence of an oxidizing agent, a redox reaction occurs, turning the iodide ion in KI (which is colorless) to iodine, I2 (which is brown).
A catalyst is a substance which increases the speed of a chemical reaction, but remains chemically unchanged at the end of the reaction.
Enthalpy change is the amount of energy involved in a reaction.
Electrolysis is the conduction of electricity by an ionic compound (an electrolyte), when molten or dissolved in water, leading to the decomposition of the electrolyte.
An atom that does not have a full valence shell will have a tendency to gain or lose valence electrons in order to achieve a stable electronic configuration.
Isotopes are atoms of the same element with the same number of protons but different number of neutrons.
Temperature, state of matter (gas/liquid/solid), relative molecular mass
Ammonium chloride, iodine crystals, dry ice, naphthalene.
Ammonia, sulfur dioxide, hydrogen chloride
– iron: in Haber Process, to manufacture ammonia
– vanadium(V) oxide: in manufacture of sulfuric acid
– platinum or rhodium: in catalytic converters
– aluminium oxide or silicon(IV) oxide: in the cracking process for producing hydrogen