What products are formed when the hydrocarbons polyethylene and polystyrene are completely combusted?

Measuring which physical property is most likely to produce the most precise results when trying to identify a substance

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

An electron moved from shell n = 2 to shell n = 1. what most likely happened during the transition? a fraction of a photon was added. a photon of energy was absorbed. a fraction of a photon was removed. a photon of energy was released.