â George Mandler has described the origins of cognitive psychology in, Ulric Neisser is credited with formally having coined the term cognitive(2002). psychology (in terms of the current understanding of cognitive psychology) in his book Cognitive Psychology, published in 1967.
The melting point of fluorine is -219 Â°C (-363 Â°F). The boiling point of fluorine is -188 Â°C (-307 Â°F).
Fluorine (symbol F) is the chemical element with atomic number 9. It is the lightest halogen. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic molecules, F2. Fluorine is the most electronegative element and is extremely reactive, requiring great care in handling.