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प्रश्न
Moving down in the second group, number of valence electrons ______.
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उत्तर
Moving down in the second group, the number of valence electrons remains the same.
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संबंधित प्रश्न
The elements Be, Mg and Ca each having two electrons in their outermost shells are in periods 2, 3, and 4 respectively of the modern periodic table. Answer the following questions, giving justification in each case:-
(i) Write the group to which these elements belong.
(ii) Name the least reactive element.
(iii) Name the element having largest atomic radius.
Write the atomic numbers of two elements 'X' and 'Y' having electronic configuration 2, 8, 2 and 2, 8, 6 respectively.
What is meant by 'group' in the modern periodic table? How do the following change on moving from top to bottom in a group?
(i) Number of valence electrons
(ii) Number of occupied shells
(iii) Size of atoms
(iv) Metallic character of element
(v) Effective nuclear charge experienced by valence electrons
An element Z has atomic number 16. Answer the following questions on Z:
- State the period and group to which Z belongs.
- Is Z a metal or a non-metal?
- State the formula between Z and hydrogen.
- What kind of a compound is this?
In the following set of elements, one element does not belong to the set. Select this element and state why it does not belong:
Oxygen, Nitrogen, Carbon, Chlorine, Fluorine
In each of the following pair, choose the atom having the bigger size:
(a) Mg (At. No.12) or Cl (At. No.17)
An element A has atomic number 14. To which period does this element belong and how many elements are there in this period.
Complete the following sentences.
The properties of the elements are a periodic function of their …………… (atomic number, mass number, reative atomic mass).
The following table represents the first period of the modern periodic table. Study the table and answer the questions that follow:
- Write the formula of the sulphate of the element with atomic number 13.
- What type of bonding will be present in the oxide of the element with atomic number 1?
- Which feature of the atomic structure accounts for the similarities in the chemical properties of the elements in group VIIA of the periodic table?
- Name the element which has the highest ionization potential.
- How many electrons are present in the valence shell of the element with atomic number 18?
- What is the name given to the energy released, when an atom in its isolated gaseous state accepts an electron to form an anion?
- What is the electronic configuration of the element in the third period which gains one electron to become an anion?
- Fill in the blanks:
The atomic size ______ as we move from left to right across the period, because the ______ increases, but the ______ remains the same.
Which of the following would weigh the least?
(Atomic masses C = 12, 0 = 16, Na = 23)
