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प्रश्न
Write the merits of the modern periodic table over Mendeleev’s Periodic table
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उत्तर
1) Elements are arranged on the basis of increasing atomic number which is more fundamental.
2) Isotopes of an element can be placed along with parent element.
3) It explains periodicity of properties of elements configuration.
4) Lanthanides and actinides are placed separately.
5) Anomalous pairs of elements like Ar and K having same atomic mass could be justified
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संबंधित प्रश्न
Why do all the elements of the same group have similar properties?
State modern periodic law.
Give two example of group 17 elements.
Is it possible to have an element having atomic number 1.5 placed between hydrogen and helium?
Which of the following statement is correct in regard to the classification of elements?
(a) Elements in modern periodic table are arranged on the basis of increasing atomic masses.
(b) Elements in Mendeleev's periodic table are arranged on the basis of increasing atomic numbers.
(c) In modern periodic table, the element nickel of lower atomic mass is kept before the element cobalt of higher atomic mass.
(d) In modern periodic table, the isotopes of chlorine having different atomic masses are kept in the same group.
The atomic particle whose number in the atoms of an element always remains the same and which forms the real basis for the modern classification of elements is:
(a) electron
(b) proton
(c) neutron
(d) meson
Which element has two shells, both of which are completely filled with electrons?
What is the major characteristic of the first elements in the periods of the periodic table? What is the general name of such elements?
State how the valency of elements varies in a group of the periodic table?
What is a group in the periodic table?
What are the periods in a periodic table? Give two characteristics of each.
An element X belongs to 3rd period and group 2 of the periodic table. State:
(a) number of valence electrons
(b) valency
(c) metal or non-metal
(d) name of the element
What are horizontal rows and vertical columns in a periodic table known as?
Name the type of elements which have two outermost shell incomplete.
An element barium has atomic number 56. Look up its position in the periodic table and answer the following question.
What will be the formula of its phosphate?
What would be the correct order if Zn, Fe, Al and Cu are arranged in increasing order of reactivity?
How many periods and groups are there in the modern periodic table?
How does number of (i) valence electrons (ii) valency; vary on moving from left to right in the second period of a periodic table?
Name an element of group 18 which can form compounds.
The horizontal rows in a periodic table are called _____.
Name the cation and the anion in the salt – calcium sulphate
Give the symbol and valency of the following element and radical.
Sodium
Give the symbol and valency of the following element and radical.
Zinc
Give the symbol and valency of the following element and radical.
Nitrogen [Nitride]
Give the chemical formula of calcium phosphate
Name the following:
The group of the Modern Periodic Table to which calcium [Ca2+] belongs.
Find the correlation:
Mendeleev’s periodic table : atomic mass : : Modern periodic table : _______
Find the correlation:
Group 13 to 18 : p block : : ______ : d block
Find the odd one out and give its explanation.
An X element with atomic number 11 and Y element with atomic number 13 belongs to the third period in the modern periodic table. With this information, give the answers of the below questions.
- Which element has more metallic character from these two elements?
- What is the valency of each X and Y elements?
- Atom size of Y element is smaller than atom size of X element? Explain?
Element ‘X’ forms a chloride with the formula XCl2, which is solid with a high melting point. X would most likely be in the same group of the periodic table as: ______
An element which is an essential constituent of all organic compounds belongs to
Arrange the following elements in the increasing order of their metallic character
| Mg, | Ca, | K, | Ge, | Ga |
Noble gases are placed in the ______ group in the modern periodic table.
Explain the position of hydrogen in the periodic table.
A part of modern periodic table is given below. On its basis, answer the following questions:
| Group No. → | 1 | 2 | 13 | 14 | 15 | 16 | 17 | 18 |
| Period ↓ | ||||||||
| 2 | A | B | ||||||
| 3 | E | D | F | C |
Write the molecular formula of the compound formed by the combination:
A and F
An element has 2 electrons in its N shell.
State its position in periodic table.
