The platinum catalyst is intended for decrease the toxicity of combustion gases. 2CO + O₂ = CO₂ 2NO = N₂ + O₂ 2NO₂ = N₂ + 2O₂ But at the same time the carbon dioxide - greenhouse gas is formed.
Light acting as 'packets' of exact amounts of energy (a particle-like quality) called quanta led to the development of quantum mechanics. Light also has wave qualities (wavelength, frequency, amplitude) which is referred to as particle-wave duality.