How many elements are on the modern periodic table?
What is 115 elements?
100
Horizontal rows are also called this.?
Periods.
100
What is on the left side of the stair step or also called metalloids?
What are metals?
100
What block is hydrogen in ?
What is the S block ?
100
What element is 1s^2.
What is helium ?
200
An English chemist, proposed the Law of Octaves which stated that elements repeated their chemical properties every eighth element.
Who is John Newlands ?
200
These are also called vertical columns..
What is a group.?
200
What is groups 3 through 12 ?
What are transition metals.?
200
What group is chromium in ?
What is the D block ?
200
What element is [Rn] 7s^2.
What is Radium ?
300
In 1869 this person placed many elements out of order based on their accepted atomic weights at the time.
Who is Mendeleev ?
300
What does the atomic number represent?
What is the number of protons located in the nucleus of an atom?
300
What is the stair step elements called?
What are metalliods?
300
What block is aluminum in ?
What is the P block ?
300
What element is [Ar] 3d^14s^2
What is Scandium ?
400
Who discovered that electrons move around a nucleus in discrete energy called orbitals. Radiation is emitted during movement from one orbital to another.
Who is Bohr ?
400
What does the decimal number represent at the bottom of the element box?
What is the atomic mass?
400
What are groups 13 through 16 called ?
What are head elements?
400
What group is bohruim ?
What is the D block ?
400
What element is [Ar] 3d^104s^24p^2.?
What is germanium?
500
Who grouped known elements into families of triads of elements with similar properties.