What name was given by mendeleev to the then undiscovered element scandium?

Name an inert radio element.

What property did mendeleev use to classify the elements?

Name two micro elements.

Name the main element of biogas.

Name two crystalline elements.

Write name of two inactive elements.

What is an element?

Which elements were discovered by Mendeleev's periodic table?

Elements of the 4th, 5th and 6th period of mendeleev's periodic table were divided into even and odd series-why?

Write four names of transuranic elements.