Chemistry
Write down the word that will correctly complete the following sentences:
(a) Relative atomic mass of a light element up to calcium is approximately …………… its atomic number.
(b) The horizontal rows in a periodic table are called ……………
(c) Going across a period left to right, atomic size ……………
(d) Moving left to right in the second period, number of valence electrons ……………
(e) Moving down in the second group, number of valence electrons ……………
Periodic Table
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Answer
(a) Relative atomic mass of a light element up to calcium is approximately twice its atomic number.
(b) The horizontal rows in a periodic table are called periods.
(c) Going across a period left to right, atomic size decreases.
(d) Moving left to right in the second period, number of valence electrons increases
(e) Moving down in the second group, number of valence electrons remains same
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Related Questions
Assertion (A): Group 17 elements are known as alkaline earth metals.
Reason (R): Group 17 elements are salt formers.
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(b) Metalloid in Period 3.
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(d) Noble gas having electronic configuration 2, 8, 8.
(e) Group whose elements have zero valency.
(f) A covalent compound formed by an element in period 2 and a halogen.
(g) Non-metallic element present in Period 3 of Groups 15 and 16.
(h) An electrovalent compound formed by an alkaline earth metal and a halogen.
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