Advertisements
Advertisements
प्रश्न
Two elements in the same position : demerit of Newland's octaves : : place for Isotopes : _______
Advertisements
उत्तर
Two elements in the same position : demerit of Newland's octaves : : place for Isotopes : Demerits of Mendeleev’s periodic table
APPEARS IN
संबंधित प्रश्न
Besides gallium, which other elements have since been discovered that were left by Mendeleev in his Periodic Table? (any two)
What were the criteria used by Mendeleev in creating his Periodic Table?
Why do you think the noble gases are placed in a separate group?
How could the Modern Periodic Table remove various anomalies of Mendeleev’s Periodic Table?
What property do all elements in the same column of the Periodic Table as boron have in common?
What property do all elements in the same column of the Periodic Table as fluorine have in common?
An atom has electronic configurations 2, 8, 7.
What is the atomic number of this element?
What was the Mendeleev's basis for the classification of elements?
In the classification of the them known elements, Mendeleev was guided by two factors. What are those two factors?
Name two elements whose properties were predicted on the basis fo their positions in Mendeleev's periodic table.
Which group of elements could be placed in Mendeleev's periodic table later on, without disturbing the order? Give reason.
State the periodic law on which Mendeleev's periodic table table was based. Why and how was this periodic law changed?
State the merits of Mendeleev's classification of elements.
What name were given by Mendeleev to the then undiscovered element scandium.
What name were given by Mendeleev to the then undiscovered element gallium?
What name were given by Mendeleev to the then undiscovered element germanium?
How do the properties of eka-aluminium element predicted by Mendeleev compare with the actual properties of gallium element?
Why did Mendeleev leave some gaps in his periodic table?
In Mendeleev's periodic table, why was there no mention of noble gases like helium, neon and argon?
State any three limitations of Mnedeleev's classification of elements.
Which group of elements was missing from Mendeleev's original periodic table?
In Mendeleev's periodic table, gap was not left for one of the following elements. This element is:
(a) gallium
(b) beryllium
(c) germanium
(d) scandium
According to Mendeleev's periodic law, the elements were arranged in the periodic table in the order of: ______
An element X forms an oxide X2O3. In which group of Mendeleev's periodic table is this element placed?
(a) group II
(b) group III
(c) group V
(d) group VIII
Mendeleev predicted the existence of certain elements not known at that time and named two of them as eka-aluminium, and eka-silicon.
(a) Name the element which has taken the place of (i) eka-aluminium, and (ii) eka-silicon
(b) Mention the period/periods of these elements in the modern periodic table.
(c) Write the group/ groups of these elements in the modern periodic table.
(d) Classify these elements as metals, non-metals or metalloids.
(e) How many valence electrons are present in the atoms of each of these elements?
The correct formula of the oxide of Eka-aluminium element predicted by Mendeleev was:
(a) EaO3
(b) Ea3O2
(c) Ea2O3
(d) EaO
State the merits of Mendeleev's classification of elements.
The elements from the zero group are called _______.
Eka boron : Scandium : : Eka Aluminum : _______
Match the columns.
| Column A | Column B |
| 1) Triads | a) Mendeleev |
| 2) Octave | b) Dobereiner |
| 3) Atomic number | c) Thomson |
| 4) Atomic mass number | d) Moseley |
| e) Newland |
Write the name.
The family of elements having zero valency.
Describe the merits of Mendeleev’s periodic table?
Which one of the following does not increase while moving down the group of the periodic table?
Match the column:
| Column ‘A’ | Column ‘B’ |
| Alkali metals | (a) Group 18 |
| Halogens | (b) Group 1 |
| Noble gases | (c) Group 17 |
