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प्रश्न
What are the elements.
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उत्तर
“Elements are pure substances made up of one kind of atoms and cannot be broken down into simpler substances.” 118 elements are there.
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संबंधित प्रश्न
The three elements having chemical symbols of Si, B and Ge are:
(a) all metals
(b) all non-metals
(c) all metalloids
(d) Si is metalloid, B is metal and Ge is non-metal
What is a period in a periodic table?
What happens to the number of valence electrons in the atoms of elements as we go down in a group of the periodic table?
State its position in the periodic table?
Write the number of protons, neutrons and electronic configuration of \[\ce{_19^39K, _15^31P}\]. Also state their position in periodic table.
An element barium has the atomic number 56. Look up its position in the periodic table and answer the following question.
Is it larger or smaller than caesium (Cs)?
How were elements arranged in the long form of the periodic table or the Modern Periodic Table?
The amount of energy released when one or more electrons is added to the neutral atom is ______
Three elements A, B and C have 3, 4 and 2 electrons respectively in their outermost shell. Give the group number to which they belong in the Modern Periodic Table. Also, give their valencies.
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:
E and B
