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प्रश्न
On which basis Mendeleev organised periodic law?
उत्तर
- Mendeleev organized the period table on the basis of atomic masses of elements.
- When he arranged the 63 elements known at that time in the increasing order of their atomic masses, he found that the chemical and physical properties of elements showed repetition after certain fixed interval.
- On the basis of this finding, he stated that ‘properties of elements are a periodic function of their atomic masses’. This is known as Mendeleev’s periodic law.
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संबंधित प्रश्न
What are the main features of Mendeleev’s periodic table?
Name three elements that have a single electron in their outermost shells.
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On what basis did mandeleev arrange the elements in his periodic table?
Name the Russian chemist who said that the properties of elements are a periodic function of their atomic masses.
What chemical properties of elements were used by Mendeleev in creating his periodic table?
List two contrasting visible characters of garden pea Mendel used for his experiment.
Write a short note.
Mendeleev’s periodic law.
Write the merits of Mendeleev’s periodic table.
Mendeleev's contributions to the concept of a periodic table laid the foundation for the Modern Periodic Table. Give reasons.
Which group of elements was missing from Mendeleev's original periodic table?
Name an element whose properties were predicted on the basis of its position in Mendeleev's periodic table.
Name two elements whose atomic weights were corrected on the basis of their positions in Mendeleev's periodic table.
How did Mendeleev arrange the elements in the periodic table?
What was the basis of Mendeleev's classification?
State the contributions made by Mendeleev towards the periodic table.
Give a reason for the following:
Mendeleev's contributions to the periodic table laid the foundation for the Modern Periodic Table.
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Write scientific reason.
There was no definitive place for isotope in 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?
An element has 12 protons. The group and period to which this element belongs is ______
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In Mendeléev’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 statement (s) about the Modern Periodic Table are incorrect
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- The elements in the Modern Periodic Table are arranged on the basis of their increasing atomic masses
- Isotopes are placed in adjoining group (s) in the Periodic Table
- The elements in the Modern Periodic Table are arranged on the basis of their increasing atomic number
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- A soft metal stored under kerosene
- An element with variable (more than one) valency stored under water.
- An element which is tetravalent and forms the basis of organic chemistry
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- An element whose thin oxide layer is used to make other elements corrosion resistant by the process of “ anodising”
Mendeléev predicted the existence of certain elements not known at that time and named two of them as Eka-silicon and Eka-aluminium.
- Name the elements which have taken the place of these elements
- Mention the group and the period of these elements in the Modern Periodic Table.
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Give an account of the process adopted by Mendeléev for the classification of elements. How did he arrive at “Periodic Law”?
