Question

Mendelev protected atomic mass and the properties of many elements that were not known at that time explain with the help of an example​

Answer 1

Answer:

According to the elements near the non predicted elements Mendeleev predicted the properties of the elements. His predictions were pretty accurate and it is a merit of Mendeleev for example he named an element not known as eka-boron later it was discovered and named scandium. It was observed that all the properties he gave were approximately equal to those discovered.

Answer 2

Answer:

Yes, Mendeleev predicted the existence of many elements that were not discovered at that time. He predicted their properties as he grouped elements with similar properties. And named those elements in the name of the preceding element in the group by adding a prefix eka.

for example germanium was named eka silicon