halogenchemistry- Andes (Wikipedia)
The Andes (/ˈændiːz/ AN-deez), Andes Mountains or Andean Mountain Range (Spanish: Cordillera de los Andes; Quechua: Anti) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is 8,900 km (5,530 mi) long and 200 to 700 km (124 to 435 mi) wide (widest between 18°S and 20°S latitude) and has an average height of about 4,000 m (13,123 ft). The Andes extend from South to North through seven South American countries: Argentina, Chile, Bolivia, Peru, Ecuador, Colombia, and Venezuela.
- Fluorine (Wikipedia)
Fluorine is a chemical element; it has symbol F and atomic number 9. It is the lightest halogen and exists at standard conditions as pale yellow diatomic gas. Fluorine is extremely reactive as it reacts with all other elements except for the light inert gases. It is highly toxic.