An 0.7700 mol sample of an ionic compound has a mass of 126.4 g. Determine the number of formula units of the compound that are present. Express answer in scientific notation.

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.

The atomic number, or number, is the described as the number of in the nucleus of an chemical element.