Question

select the correct scientist for each of the following advances in creating the modern periodic table. organized elements into four groups based on properties: developed the law of octaves: arranged elements by atomic number:

Explanation:

1. Johann Wolfgang Döbereiner organized elements into groups of three (triads) based on properties, but if we consider grouping into four - groups based on properties, there is no widely - known single scientist specifically for this. However, Döbereiner was an early pioneer in element grouping.
2. John Newlands developed the law of octaves, which stated that when the elements are arranged in order of increasing atomic weight, every eighth element has similar properties, similar to the notes in an octave in music.
3. Henry Moseley arranged elements by atomic number. He discovered that the square root of the frequency of X - rays emitted by an element was proportional to its atomic number, which led to the modern arrangement of elements in the periodic table by atomic number.

Answer:

1. Johann Wolfgang Döbereiner
2. John Newlands
3. Henry Moseley