Consider four atoms from the second period: lithium, beryllium, boron, carbon, and nitrogen. which of these elements has the lowest electronegativity value?

How have the greenhouse gasses increased from the year 2000 to 2018

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 number to the right of an element's symbol (ex. c-12) identifies the of an isotope.