An excess of a divalent metal M was dissolved in a limited volume of hydrochloric acid; if 600cm³ of
hydrogen were liberated at stp, determine the
mass of the metal that produced this volume of
hydrogen (M= 24, H=1, GMV-22.40ms)
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The human eye contains a molecule called 11-cis-retinal that changes shape when struck with light of sufficient energy. the change in shape triggers a series of events that results in an electrical signal being sent to the brain that results in vision. the minimum energy required to change the conformation of 11-cis-retinal within the eye is about 164 kj/mol.