Answer:
photoelectric effect, phenomenon in which electrically charged particles are released from or within a material when it absorbs electromagnetic radiation. The effect is often defined as the ejection of electrons from a metal plate when light falls on it.
chemistry is used in medicine and water and air are chemical
The potassium will donate one of its valence electrons
The equivalence point of a titration is equal to its stoichiometric equivalents of analyte and titrant.
Depending on the concentration of titrant we could be adding little excess of it and this may result in persistence of color of solution. After continuous stirring for a while the excess titrant may react with dissolved CO₂ in air and thus decolorizing the solution.
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