How many elements are on the modern periodic table?
118
15
In the early 1800s, the method for arranging the elements began when a scientist described elements and compounds in terms of relative weights. Who was the scientist that did this?
John Dalton
15
One of the major developments that allowed for what became known as the periodic table was the discovery and measurements of:
atomic masses
15
Who was the German scientist that created a table that showed 28 elements systematically arranged by valence into vertical columns. The atomic weights of these elements increase by similar amounts when going step-wise from left to right
Julius Meyer
15
T/F: In 1865, a periodic table was published by English chemist William Odling, and it described a systematic arrangement of 45 elements. However, some elements were omitted without any reasonable explanation.
False
15
T/F: John Newlands created a periodic table based on the law of octaves.
True
15
Who was the Russian chemist that created a periodic table that left placeholders for elements that he predicted would eventually be discovered rather than omitting elements where the periodic trends did not seem to fit?
Dmitri Mendeleev
15
Who is the "Father of the Periodic Table?"
Dmitri Mendeleev
15
T/F: Mendeleev and Moseley are credited with formulating the modern periodic law, which states that when elements are arranged in order of increasing atomic number, there is a periodic repetition of their chemical and physical properties
True
15
T/F: Characteristic properties of the elements could be related to atomic mass and atomic number.
True
15
T/F: Ordering the elements by atomic number instead of atomic mass cleared up some of the discrepancies found in older periodic tables and provided the basis for our current table of the elements.
