Halogens
the most reactive of all the elements
What is Fluorine?
the element with an atomic number of 2
What is Helium?
this element is the most abundant in the human body
What is Oxygen?
this makes up 78% of the volume of air
What is Nitrogen?
forms of the same element that differ in their properties but exist in the same physical state
What is an allotrope?
one of the most versatile elements
What is Chlorine?
this element is used in airport runway and approach lighting
What is Krypton?
this element is found in both DNA and RNA
What is Phosphorus?
lightning is a small part of this element's cycle
What is the Nitrogen Cycle?
the most important method of preparing hydrogen in the US
What is steam reforming?
this is the only radioactive element of the halogens
What is Astatine?
this noble gas can be found in basements and can be harmful
What is Radon?
an alcohol solution of this element is used as an antiseptic for cuts
What is Iodine?
most fertilizers contain these two elements
What are Phosphorus and Nitrogen?
the total number of elements in chapter 10 of the textbook
What is 16?
this reason prevents the halogens from being found naturally, in their free state
What is too reactive?
instead of Nitrogen, this element is used in the air used by deep-sea divers
What is Helium?
your teeth are grateful for this element
What is Flourine?
sulfur is easily obtained from this mineral
What is gypsum?
tritium is the third isotope of this element
What is Hydrogen?
if you are concerned about the ozone layer, don't use these
What are chlorofluorocarbons?
of all the noble gases, these two have never been made into stable compounds
What are Helium and Neon?
this element is vital in metabolism
What is ozone?
phosphoric acid, in formula form
What is H3PO4?
this form of sulfur tarnishes silver
What is hydrogen sulfide?