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प्रश्न
In Mendeleev’s periodic table eka- silicon was later named as _______.
विकल्प
scandium
gallium
germanium
thorium
उत्तर
In Mendeleev’s periodic table eka- silicon was later named as germanium.
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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 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?
State any three demerits of Mendeleev’s periodic table.
On what basis elements are arranged in periodi table now?
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 were the two criteria used by Mendeleev to classify the elements in 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.
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.
Answer the following question:
Name two elements having a single electron in their outermost shell.
What are the demerits of Mendeleev’s periodic table?
Give a reason for the following:
Mendeleev's contributions to the periodic table laid the foundation for the Modern Periodic Table.
Write the molecular formula of the oxide of any one of the elements in Mendeleev’s periodic table.
Which two elements show an ambiguity regarding their sequence in Mendeleev’s periodic table?
While designing the periodic table, Mendeleev considered the chemical and physical properties of the elements.
Write scientific reason.
Mendeleev kept vacant places in the periodic table.
State Mendeleev’s Periodic Law.
What are the limitations of Mendeleev's periodic table?
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 oxide is most basic?
Eka-aluminium and Eka-silicon are known as ______
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
- The elements in the Modern Periodic Table are arranged on the basis of their decreasing atomic number
- 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
On moving from left to right in a period in the periodic table, the size of the atom.
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.
Properties of the elements are given below. Where would you locate the following elements in the periodic table?
- 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
- An element which is an inert gas with atomic number 2
- An element whose thin oxide layer is used to make other elements corrosion resistant by the process of “ anodising”
Give an account of the process adopted by Mendeléev for the classification of elements. How did he arrive at “Periodic Law”?
