Determine the percentage composition of hydrogen and oxygen in ammonium sulphate, (NH4)2SO4.

Why is an elements atomic mass not listed as a whole number on the periodic table

This classification of drug typically changes the brain's chemistry and reduces its ability to create its own endorphins.

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.