If a physical change has taken place, which of these is most likely true? Group of answer choices

A permanent change has taken place.

The changed substance retains its unique properties.

Atoms rearrange to form a new substance.

The molecular composition of a substance changes.

The dissociation energy of a molecule is the energy required tobreak apart the molecule into its separate atoms. the dissociationenergy for a particular molecule is 5.48 x 10-18 j.suppose that this energy is provided by a single photon. determinethe (a) wavelength and (b) frequency of the photon

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.

What quantity do units represent in value