Question

what is the correct chronological order of scientists contributing to the modern periodic table?
○ lavoisier, newlands, moseley, dobereiner, and mendeleev
○ lavoisier, dobereiner, newlands, mendeleev, and moseley
○ moseley, mendeleev, newlands, dobereiner, and lavoisier
done ✔
one of the following properties was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version. which property fits this description?
○ atomic number
○ atomic mass
○ chemical properties
done ✔

Explanation:

First Question (Chronological Order of Scientists):

1. Lavoisier: Early work on elements (late 18th century).
2. Dobereiner: Triads (early 19th century).
3. Newlands: Octaves (mid - 19th century).
4. Mendeleev: Periodic table (late 19th century).
5. Moseley: Atomic number (early 20th century).

So the correct order is Lavoisier, Dobereiner, Newlands, Mendeleev, and Moseley.

• Atomic number: Used in modern periodic table (arranged by Moseley).
• Atomic mass: Originally used (by Mendeleev), but due to isotopes and other factors, modern table uses atomic number.
• Chemical properties: Still relevant for grouping (same group has similar chemical properties).

So the property is atomic mass.

Answer:

B. Lavoisier, Dobereiner, Newlands, Mendeleev, and Moseley

Second Question (Property No Longer Used):