Fill in the Blanks Unit 1 Periodic Table Reading AssignmentOnline version Fill-In-the-Blanks: Prior to doing the "Periodic Table Project Based Assignment" you are to complete this reading assignment. by Eric D Norman 1 element elements element elements atoms elements elements element atom Primary substances , called , build all the materials around you . There are more than 109 different known today . The are composed of , the smallest units that are characteristic of a particular . Some occur in different forms , such as graphite and diamond for the carbon . But whatever the form of the , it is composed of its characteristic . 2 protons negatively positively Atoms 1 electrons 0 neutrons neutral electrons Protons neutrons are made of even smaller particles of matter called subatomic particles . A large number of subatomic particles are now known , but we are primarily interested in the ( p ) , ( n ) , and ( e ) . are charged particles ( + ) , are charged particles ( ? 1 ) , and are ( charge = ) . 3 protons protons atomic 26 two one six atomic number mass Atoms of a particular element have one feature in common : the number of in the nucleus . The number of , called the ( Z ) is unique for each element . Atoms of the element hydrogen always have proton in their nuclei , while atoms of the next element , helium , always have protons in their nuclei . Atoms of the element carbon similarly contain protons , and atoms of iron have protons . The sum of the number of protons and neutrons in the nucleus of an atom is called the . 4 properties periodic elements periods groups periods table groups The is a listing , in chart form , of the known elements . Long ago , it was recognized that certain shared similar , and when the property , such as density , was plotted against atomic mass , a repeating , or " periodic " pattern was observed . The modern periodic table is arranged in horizontal rows ( also called ) and vertical columns called or families . The are numbered from 1 to 7 . The are numbered 1 through 18 , excluding the lower , separate rows of elements ( the lanthanides and actinides ) below the main table .
New game