Question

The close match between Mendeleev's __________and the ____________of new elements showed how useful his periodic table could be.

a) observations / development
b) predictions / discovery
c) postulates / formulation
d) classifications / research

Answer 1

The close match between Mendeleev's predictions and the discovery of new elements demonstrated the usefulness of his periodic table.

Step-by-step explanation:

The close match between Mendeleev's predictions and the discovery of new elements showed how useful his periodic table could be. Mendeleev arranged elements in a table based on atomic masses and intentionally left gaps for elements that were predicted but not yet discovered. When these elements were discovered and found to have properties predicted by Mendeleev, his periodic table became universally accepted.