(a) How do the properties of eka-aluminium element predicted by Mendeleev compare with the actual properties of gallium element? Explain your answer.
(b) What names were given by Mendeleen to the then undiscovered elements (i) Scandium (ii) gallium, and (iii) germanium?

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

The three elements predicted by Mendeleev from the gaps in his periodic table were known as eka-boron, eka-aluminium and eka-silicon. What names were given to these elements when they were discovered later on?

Did Mendeleev predict the properties of scandium and gallium even when these elements were not discovered ?

How do the positions of elements in the periodic table help you to predict its chemical properties ? Explain with and example .

Mendeleev was a Russian chemist, who contributed the most for the development of periodic table of elements wherein the elements were arranged on the basis of their fundamental property, the atomic mass and also on the similarity of chemical properties. Only 63 elements were known at his time. He arranged the 63 elements in the increasing order of their atomic masses and found that there was a periodic recurrence of elements with similar physical and chemical properties, He observed that elements with similar properties fall in the same vertical column. These vertical columns are called groups and horizontal rows of elements are called periods. Mendeleev predicted the existence of certain elements not known at that time and named two of them as Eka-silicon and Eka-aluminium. How do we classify these newly discovered elements (eka-aluminium and eka-silicon)?

Name the element whose properties can be predicted on the basis of its position in the periodic table given by Mendeleev's.

What is long form periodic table ? How do the properties of elements vary in groups and periods of the periodic table? Name the elements of zero group.