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प्रश्न
Choose the correct option and rewrite the statement.
The number of electrons in the outermost shell of alkali metals is _______.
पर्याय
1
2
3
7
उत्तर
The number of electrons in the outermost shell of alkali metals is 1.
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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.
State whether the following statement is true of false:
The elements in a group have consecutive atomic numbers.
Rewrite the following statement after correction, if necessary:
Isotopes are the elements of the same group.
The element which forms a basis oxide has the atomic number of:
(a) 18
(b) 17
(c) 14
(d) 19
The element X forms a compound X2Y. Suggest an element that Y might be and give reasons for your choice.
An element X from group 2 reacts with element Y from group 16 of the periodic table.
(a) What is the formula of the compound formed?
(b) What is the nature of bond in the compound formed?
Give a reason why elements need to be properly classified.
State whether true or false. If false, correct the statement.
Metals can gain electrons.
If the distance between two Cl atoms in a Cl2 molecule is 1.98Å, then the radius of the Cl atom is ______.
Among the given species A–, A+, and A, the smallest one in size is ______.
Identify the bond between H and F in the HF molecules.
Consider the following elements 20Ca, 8Or 18Ar, 16S, 4Be, 2He
Which of the above elements would you expect to be in group 16 of the Periodic Table?
The atom of an element has electronic configuration 2, 8, 7. To which of the following elements would it be chemically similar?
Which of the following is a transition element?
Element ‘A’ has electronic configuration 2, 7; ‘B’ has electronic configuration 2, 8, 5 and ‘C’ has electronic configuration 2, 8, 7. Which two elements will exhibit similar chemical properties?
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
Which of the following metals have low melting and boiling point?
Relate the names of the following scientists with the statements given below.
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Justify. Element 'X' forms an oxide with the formula X2O3 which is a solid with a high melting point. ‘X’ would most likely be placed in the group of the Periodic Table as Al.
