(a) What is meant by (i) a group, and (ii) a period, in a periodic table?(b) How many periods and groups are there in the long form of periodic table? (c) Give two examples each of (i) group 1 elements (ii) group 17 elements (iii) group 18 elements.
(a)(i) Groups are the vertical columns in the periodic table.
(ii) A period is the horizontal rows of elements in the periodic table.
(b) There are seven periods and eighteen groups in the long form of the periodic table.
(c)(i) Two examples of Group 1 elements are Lithium and Sodium .
(ii) Two examples of Group 17 elements are Fluorine and Chlorine.
(iii) Two examples of Group 18 elements are Neon and Argon.
Related Articles (a) How does the electropositive character of elements change on going down in a group of the periodic table?(b) State how the valency of elements varies (i) in a group, and (ii) in a period, of the periodic table.
Carbon, Group (14) element in the Periodic Table, is known to form compounds with many elements. Write an example of a compound formed with(a) chlorine (Group 17 of Periodic Table)(b) oxygen (Group 16 of Periodic Table)
(a) What is a group in the periodic table? In which part of a group would you separately expect the elements to have (i) the greatest metallic character (ii) the largest atomic size?(b) In what respects do the properties of group 1 elements differ from those of group 17 elements? Explain with examples by taking one element from each group. (c) From the standpoint of atomic structure, what determines which element will be the first and which the last in a period of the periodic table? (d) Explain why, the properties of elements are repeated after 2, 8, 18, and 32 elements in the periodic table. (e) What are the advantages of the periodic table?
Consider the following elements:20Ca, 8O, 18Ar, 16S, 4Be, 2He Which of the above elements would you expect to be: (i) very stable? (ii) in group 2 of the periodic table? (iii) in group 16 of the periodic table?
(a) What is the usual number of valence electrons and valency of group 18 elements of the periodic table?(b) What happens to the number of valence electrons in the atoms of elements as we go down in a group of the periodic table?
An element X is forming acidic oxide. Its most probable position in the modern periodic table is(A) Group 1 and Period 3 (B) Group 16 and Period 3 (C) Group 17 and Period 3 (D) Group 2 and Period 3
An element X forms an oxide X2O3. In which group of Mendeleev's periodic table is this element placed?(a) group II (b) group III (c) group V (d) group VIII
How does the valency of elements vary in going down a group of the periodic table?
Give examples of alkaline metals present in Group-1 in the Periodic Table.
Fill in the following blanks with suitable words:(a) The basis for modern periodic table is ______. (b) The horizontal rows in a periodic table are called ______. (c) Group 1 elements are called ______. (d) Group 17 elements are known as ______. (e) Group 18 elements are called ______. (f) According to Newlands’ classification of elements, the properties of sulphur are similar to those of oxygen because sulphur is the ______ element starting from oxygen.
Which of the following statement (s) about the Modern Periodic Table are incorrectThe elements in the Modern Periodic Table are arranged based on their decreasing atomic numberThe elements in the Modern Periodic Table are arranged based on their increasing atomic massesIsotopes are placed in adjoining group (s) in the Periodic TableThe elements in the Modern Periodic Table are arranged based on their increasing atomic number(a) (i) only(b) (i), (ii) and (iii)(c) (i), (ii) and (iv) (d) (iv) only
An element ‘X’ is forming an acidic oxide. Its position in modern periodic table will be(a) Group 1 and Period 3 (b) Group 2 and Period 3(c) Group 13 and Period 3 (d) Group 16 and Period 3
Atomic number of a few elements are given below 10, 20, 7, 14(a) Identify the elements(b) Identify the Group number of these elements in the Periodic Table(c) Identify the Periods of these elements in the Periodic Table(d) What would be the electronic configuration for each of these elements?(e) Determine the valency of these elements.
What is the atomic number of element of period 3 and group 17 of the Periodic Table?1041721
Based on the group valency of elements write the molecular formula of the following compounds giving justification for each:(i) Oxide of first group elements.(ii) Halide of the elements of group thirteen, and(iii) Compound formed when an element, A of group 2 combines with an element, B of group seventeen.
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