Question

Which answer choice correctly describes how Mendeleev predicted new elements?

Mendeleev organized elements so that their atomic mass increased from right to left.
Mendeleev arranged elements into a table and left gaps and descriptions of expected properties based on inconsistencies in atomic number.
Mendeleev organized elements into a table and left gaps based on patterns he saw.
Mendeleev arranged elements into groups with similar physical properties.

Answer 1

The answer is Mendeleev arranged elements into a table and left gaps and descriptions of expected properties based on inconsistencies in atomic number.

In Mendeleev 's periodic table, a large part, is attributed to the gaps which he predicted would contain undiscovered elements with predictable properties. That is the main reason of the success of his periodic table.