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Question
Match the atomic number with the following:
A rare gas.
Options
19
15
8
4
2
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Solution
2
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RELATED QUESTIONS
The atomic numbers of four elements P, Q, R and S are 6, 8, 14 and 16 respectively. Out of these, the element known as metalloid is:
(a) P
(b) Q
(c) R
(d) S
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(b) Elements in Mendeleev's periodic table are arranged on the basis of increasing atomic numbers.
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(d) In modern periodic table, the isotopes of chlorine having different atomic masses are kept in the same group.
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Write an Explanation.
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Give the criteria on the basis of which elements are placed (i) in a group and (ii) in a period in the modern periodic table. The atomic number of an element is 16. According to the criteria, in which group and period it should be placed?
