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प्रश्न
State whether the following statement is true of false:
The elements in a group have consecutive atomic numbers.
उत्तर
False
The elements in a period have consecutive atomic numbers.
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संबंधित प्रश्न
An element P (atomic number 20) reacts with an element Q (atomic number 17) to form a compound. Answer the following questions giving reason:
Write the position of P and Q in the Modern Periodic Table and the molecular formula of the compound formed when P reacts with Q.
The element which forms a basis oxide has the atomic number of:
(a) 18
(b) 17
(c) 14
(d) 19
Alkaline earth metals have valency 2. This means that their position in the modern periodic table is in ______.
In which block of the modern periodic table are the nonmetals found?
(a) How is possible valency of an element determined from the electronic configuration of its atom ?
(b) Determine the valency of an element X whose atomic number is 15.
How did the early chemists classify elements?
What property forms the basis of identification?
Which of the following is a transition element?
The element with atomic number 26 will be found in group ______
Complete the following cross word puzzle
Across:
(1) An element with atomic number 12.
(3) Metal used in making cans and member of Group 14.
(4) A lustrous non-metal which has 7 electrons in its outermost shell.
Down:
(2) Highly reactive and soft metal which imparts yellow colour when subjected to flame and is kept in kerosene.
(5) The first element of second Period
(6) An element which is used in making fluorescent bulbs and is second member of Group 18 in the Modern Periodic Table
(7) A radioactive element which is the last member of halogen family.
(8) Metal which is an important constituent of steel and forms rust when exposed to moist air.
(9) The first metalloid in Modern Periodic Table whose fibres are used in making bullet-proof vests
