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प्रश्न
At the time of Mendeleev _______ elements were known.
विकल्प
56
65
63
118
उत्तर
At the time of Mendeleev 63 elements were known.
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संबंधित प्रश्न
Use Mendeleev’s Periodic Table to predict the formulae for the oxides of the following elements:
K, C, Al, Si, Ba.
Name three elements that have a single electron in their outermost shells.
Name two elements that have two electrons in their outermost shells.
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?
By considering their position in the Periodic Table, which one of the following elements would you expect to have maximum metallic characteristic?
State any three demerits of Mendeleev’s periodic table.
On what basis elements are arranged in periodi table now?
On what basis did mandeleev arrange the elements in his periodic table?
State whether the following statement is true of false:
According to Mendeleev's periodic law, the properties of elements are a periodic function of their atomic numbers.
What chemical properties of elements were used by Mendeleev in creating his periodic table?
(a) Write its electronic configuration and determine its valency.
(b) Is it more reactive or less reactive than Ca (atomic number 20)? Justify your answer giving reason.
(c) Is it a metal or a non-metal?
(d) Write the formula of its oxide.
Write a short note.
Mendeleev’s periodic law.
Write the merits of Mendeleev’s periodic table.
State Mendeleev's periodic law.
Why did Mendeleev's leave some gaps in his periodic table os elements? Explain your answer with an example.
Name two elements whose atomic weights were corrected on the basis of their positions in Mendeleev's periodic table.
How many elements were known at the time of Mendeleev's classification of elements?
Answer the following question:
Name two elements having a single electron in their outermost shell.
What was the basis of Mendeleev's classification?
How did Mendeleev's arrangement of elements correlate with the periodicity of the properties of elements?
State the contributions made by Mendeleev towards the periodic table.
What were the defects and anomalies in Mendeleeff's Periodic Table and how are they resolved by Moseley?
According to Mendeleev’s periodic law, properties of elements are periodic function of their _______.
According to Mendeleev’s periodic law properties of elements are ______.
Write scientific reason.
There was no definitive place for isotope in Mendeleev’s periodic table.
On which basis Mendeleev organised periodic law?
What are the limitations of Mendeleev's periodic table?
In Mendeleev’s Periodic Table, gaps were left for the elements to be discovered later. Which of the following elements found a place in the Periodic Table later?
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
Eka-aluminium and Eka-silicon are known as ______
According to Mendeléev's Periodic Law, the elements were arranged in the periodic table in the order of
In Mendeléev’s Periodic Table the elements were arranged in the increasing order of their atomic masses. However, cobalt with atomic mass of 58.93 amu was placed before nickel having an atomic mass of 58.71 amu. Give reason for the same.
Give an account of the process adopted by Mendeléev for the classification of elements. How did he arrive at “Periodic Law”?
