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प्रश्न
What are the elements.
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
Fill in the following blank with suitable word:
The horizontal rows in a periodic table are called ...............
Which of the following statement about the modern periodic table is correct?
(a) It has 18 horizontal rows known as periods.
(b) It has 7 vertical columns known as periods.
(c) It has 18 vertical columns known as groups.
(d) It has 7 horizontal rows known as groups.
Explain why All the elements of a group have similar chemical properties.
What are the groups in a periodic table? Give two characteristics of each.
Give the symbol and valency of the following element and radical.
Sulphur [Sulphide]
State the number of elements in Period 2 of the Periodic Table.
On moving from left to right in a period in the periodic table, the size of the atom ______
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.
Name the non-metals in the first twenty elements.
Give reason for the following:
Inert gases do not form ion.
