Advertisements
Advertisements
प्रश्न
Why did Mendeleev's leave some gaps in his periodic table os elements? Explain your answer with an example.
उत्तर
He left gaps in the table for the undiscovered elements. He discovered the properties of such elements with the help of neighboring elements.
He discovered eka-silicon with atomic mass of 72 which was later named Germanium with atomic mass 72.6.
APPEARS IN
संबंधित प्रश्न
Name three elements with filled outermost shells.
Helium is an unreactive gas and neon is a gas of extremely low reactivity. What, if anything, do their atoms have in common?
State any three demerits of Mendeleev’s periodic table.
Why did Mendel choose garden pea for his experiments? Write two reasons.
State Mendeleev's periodic law.
Beryllium : alkaline earth metal : : sodium: _______
At the time of Mendeleev, the number of elements known was ______
The properties of eka-aluminum predicted by Mendeleev are the same as the properties of a later discovered elements: ______
Which of the following are the characteristics of isotopes of an element?
(i) Isotopes of an element have the same atomic masses
(ii) Isotopes of an element have the same atomic number
(iii) Isotopes of an element show the same physical properties
(iv) Isotopes of an element show the same chemical properties
Write the formulae of chlorides of Eka-silicon and Eka-aluminium, the elements predicted by Mendeléev.
