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प्रश्न
What is the number of valence electrons in the atoms of first elements in a period?
उत्तर
The number of valence electrons in the atoms of first elements in a period is 1.
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संबंधित प्रश्न
Write the names given to the vertical columns and horizontal rows in the Modern Periodic Table. How does the metallic character of elements vary on moving down a vertical column? How does the size of atomic radius vary on moving left to right in a horizontal row? Give reason in support of your answer in the above two cases.
Fill in the following blank with suitable word:
Group 1 elements are called ...............
What is meant by a period, in a periodic table?
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
Which of the following statement is correct in regard to the classification of elements?
(a) Elements in modern periodic table are arranged on the basis of increasing atomic masses.
(b) Elements in Mendeleev's periodic table are arranged on the basis of increasing atomic numbers.
(c) In modern periodic table, the element nickel of lower atomic mass is kept before the element cobalt of higher atomic mass.
(d) In modern periodic table, the isotopes of chlorine having different atomic masses are kept in the same group.
Which element has two shells, both of which are completely filled with electrons?
The atomic numbers of the three elements X, Y and Z are 2, 6 and 10 respectively.
(i) Which two elements belong to the same group?
(ii) Which two elements belong to the same period?
Give reasons for your choice.
Name two elements in halogens.
Answer the following in respect of element `31/15 P `
To which group and period does it belong?
Answer the following question.
How it can be proved that the basic structure of the Modern Periodic Table is based on the electronic configuration of atoms of different elements?
