PERIODIC CLASSIFICATION OF ELEMENTS 10

PRACTICE PAPER

CHEMISTRY (2020)
      PERIODIC CLASSIFICATION OF ELEMENTS

CLASS X

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I. Very short answer type questions: 

1. Write the number of vertical columns in the modern periodic table. What are these columns called? 
2. Write the number of horizontal rows in the modern periodic table. What are these rows called?
3. Write the atomic numbers of two elements X and Y having electronic configuration 2, 8, 2 and 2, 8, 6 respectively.
4. Write any one difference between the electronic configuration of group 1 and group 2 elements.
5. There are 7 electrons in the outermost L shell of an element. Predict the period and group in the periodic table these elements belong to.
6. The atomic number of three elements X, Y and Z are 3, 11 and 17 respectively. State giving reasons which two elements will show similar chemical properties.
7. Write two reasons responsible for the late discovery of noble gases.
8. What are cations and anions?
9. Why hydrogen should be placed in group 1.
10. Name any two elements that have two electrons in their valence shells.
11. Name two elements of the first period in the Modern Periodic Table.
12. On which side of the periodic table do you find metal and non-metal?
13. What is the similarity in the valency of all the elements of group 1 in the modern periodic table?
14. State the similarity in the electronic configuration of all the elements present in group 1 of the periodic table.
15. How does the electronegativity changes as we move from left to right across a period?
16. An element has atomic number 32 which period of the periodic table does it belong?
17. Mention any two trends exhibit by elements when we go from left to right across the period of the periodic table.

II. Short Answer Type Questions: 

1. Arrange the following elements in the descending order of atomic size and give reasons for your answer. Mg, Cl, P, and Ar ( The atomic number of the above elements are 12, 17, 15, 18 respectively.
2. Mention any two trends exhibit by elements when we go from left to right across the period of the periodic table.
3. Elements in the periodic table show periodicity of properties. List any four such properties.
4. The atomic number of three elements A, B, and C are 12,18 and 20 respectively. State giving reasons, in which two elements will show similar properties.
5. List any two properties of the element belonging to the first group of the modern periodic table.
6. (a) The atomic number of Mg and Al are 12 and 13 respectively. Write down their electronic configuration.
   (b) Mention the period of the modern periodic table to which the above two elements belong. Give reasons for your answer.
7. Three elements X, Y, and Z belong to the 17th group but 2nd, 3rd and 4th periods respectively. The number of valence electrons in Y is 7. Find the number of valence electrons in X and Z.
8. (a)The atomic radius of hydrogen at 37 pm. Express it in meters.
   (b) How does atomic size vary in the group and in a period?
9. Nitrogen and phosphorus belong to group 15 of the periodic table. Write the electronic configuration of these two elements. Which of these will be more electronegative and why?
10. How does the metallic character of the elements vary: 
    (i) in a group (ii) in a period of the modern periodic table?
11. Na, Mg, Al, and P belong to the 3rd period but are placed in the 1st 2nd 13th and 15th group. Number of shells occupied in Mg is 3. What is the number of occupied shells in Na Al and P?. Give reasons for your answer.
12. Out of the elements X and Y which has a bigger atomic radius? Give reasons to justify your answer.
    (i) X has atomic number 18 and atomic mass 40.
    (ii)Y has atomic number 20 and atomic mass 40.
13. Element Y with atomic number 3 combines with element X with atomic number 17.
    (a) What would be the formula of the compound?
    (b)What is the electronic configuration of an element Z with atomic number 10? What will be its valency?
14. How does the tendency to lose electrons changes as we go from:
    (a) left to right across a period? (b) Down a group?
15. (a) What are metalloids?
    (b) Name any four metalloids.
16. Study the following tables in which position of six elements A, B, C, D, E, and F are shown as they are in the modern periodic table. 

    Group-> Period	1	2	3-12	13	14	15	16	17	18
    2 3	A			D	E	B			C F

    On the basis of the above table answer the following questions?
    (i) Name the element which forms only covalent compounds.
    (ii) Name the element which is a metal with valency 3
    (iii) Name the element which is a nonmetal with valency 3
    (iv) Out of D and E which is bigger in size and why? And write a common name of family C an F. 
17. (a) How does the tendency to gain electrons changes as we go down the group?  Give reason.
    (b) Given below is a part of the periodic table. How does the valency vary as we move vertically downwards from Li to Fr. Give reasons.

    Li	Be
    Na
    K
    Rb
    Cs
    Fr Ra	Ra

    Write the common name for the family to which the elements C and F belong.
18. What is meant by a group in the modern periodic table? How do the following change in moving from top to bottom in a group?
    (i) Number the valence electrons.
    (ii) A number of occupied shells.
    (iii) Size of atoms
    (iv) Metallic character of elements
    (v) Effective nuclear charge experienced by valence electrons.
19. The element 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 metal.
    (iii) Name the element having the largest atomic radius.
20. Based on the group valency of elements state the formula for the following giving justification for each:
    (i) Oxides of first group elements.
    (ii) Halides of the element of group 13 and
    (iii) Compound formed when an element of group 2 combines with an element of group 16.
21. Name:
    (i) Two elements that have a single electron in their outermost shell
    (ii) Two elements that have two electrons in the outermost shell
    (iii) Two elements with a filled outermost shell.
22. (i) Who proposed modern periodic law?
    (ii) What was the basis of arranging the element in it?
    (iii) State the modern periodic table.
23. Given below are atomic radii of the same elements of the second period.
    Element -                               B   O    N   C
    At.rad.in pm (picometre)        88  66  74  77            1Pm = 10^-12m.
    (i) Arrange them in decreasing order of their atomic radii.
    (ii) Are the elements now arranged in the pattern of a period in the Periodic Table?
    (iii) Which elements have the largest and the smallest atoms?
    (iv) How does the atomic radius change as you go from left to right in a period?
24. (i) Which two criteria did Mendeleev use to classify the elements in his periodic table?
    (ii) State Mendeleev periodic table.
    (iii) Why is it not possible to give a fixed position to hydrogen in Mendeleev's periodic table?
25. (a) Define the following terms: (i) Valency   (ii) Atomic size
    (b) How do the valency and atomic size of the elements vary while going from left to right along with a periodic table in the modern periodic table?
26. Write the number of periods in the modern periodic table has. How do the valency and metallic character of elements vary on moving from left to right in a period? How do the valency and atomic size of the elements vary down a group?
27. The atomic number of Mg and Al are 12 and 13 respectively. Write down their electronic configuration.

III. Long Answer Type Questions: 

1. An element X reacts with an element Y to form a compound. (Atomic number 17 and 20).
   (i) Write the position of this element in the modern periodic table.
   (ii) Write the formula of the compound formed.
   (iii) Justify your answer in each case.
2. How does the metallic character of a metal depend on the size of an atom?
3. The elements in Li, Na, and K each having one valence electrons are in periods 2, 3 and 4 respectively of the modern periodic table.
   (i) In which group of the periodic table should they be?
   (ii) Which one of them is the least reactive?
   (iii) Which one of them has the largest atomic radius?
   Give the reason to justify your answer in each case.
4. (a) Why are noble gases so called?
   (b) Name any two noble which are found in the atmosphere?
   (c) Why the noble gases are placed in a separate group?
5. Four elements are A, B, C and D along with their electronic configurations are given below:
   
   

   Elements	A	B	C	D
   Electronic configuration	2,1	2,8	2,8,1	2,8,8

    Now answer the following questions:
   (i) Which two elements belong to the same period?
   (ii) Which two elements belong to the same group?
   (iii) Which element out of A and C is more reactive and why?
6. Four elements P, Q, R, and S have atomic numbers 12, 13, 14, and 15 respectively. Answer the following questions giving reasons:
   (i) What is the valency of Q?
   (ii) Classify these elements as metals and non-metals.
   (iii) Which of these elements will form the most basic oxide?
7. Consider two elements A and B atomic number 17 and 19.
   (i) Write the position of these elements in the modern periodic table giving justification
   (ii) Write the formula of the compound formed when A combines with B.
   (iii) Draw the electrons dot structure of the compound and state the nature of the bond formed between the two elements.
8. An atom has electronic configuration 2, 8, 2.
   (i) What is the atomic number of this element?
   (ii) What is its valency?
   (iii) To which of the following elements would it be chemically similar and why?  Be-4,  O-8 
9. Three elements X, Y, and Z have atomic numbers 7, 10 and 14 respectively.
   (i) Identify the group number of these elements in the periodic table.
   (ii) Mention one unique feature each of elements Y and X.
   (iii) Which of the above two elements belongs to the same period?
10. Two elements X and Y belong to groups 1 and 2 respectively in the same period of the periodic table. Compare these elements with respect to
    (i) Number of electrons in the outermost orbit
    (ii) Their valencies
    (iii) Metallic character
    (iv) Their atomic size
    (v) The formula of the chloride
    (vi) The formula of their Sulphate.
11. Using the given part of the periodic table answer the following questions with reason:
    (i) Name the element having the smallest atomic size.
    (ii) Write the electronic configuration of element E.
    (iii) Identify the elements which have similar physical and chemical properties as the element Y.

    Group→ Period↓	1	2	13	14	15	16	17	18
    3	X		B	C	E	D
    4	Y
    5	Z

13. (a) How does the electronic configuration of an atom related to its position in the modern periodic table?
    (b) Would you place the two isotopes of chlorine Cl-35 and Cl-37 in different slots of the periodic table because of their different atomic mass or in the same slot because their chemical properties are the same? Justify your answer.
14. (b) What are the two criteria used in the development of Modern periodic table?
    (c) State the position of (i) metal (ii) nonmetal or (iii) metalloid in the periodic table. 
15. An element X ( 2, 8, 2 ) combine separately with SO₄^2-, PO₄^3-
    (i) Write the formula of the two compounds so formed
    (ii) To which group of the modern periodic table does the element X belongs?
    (iii) Will it form a covalent or ionic compound? Give reasons.
16. Which element has:
    (i) Two shells both of which are completely filled with elements?
    (ii) Electronic configuration 2, 8, 2?
    (iii) A total of three shells, with four electrons in its valence shell?
    (iv) A total of two shells, with three electrons in its valence shell?
    (v) Twice as many electrons in its second shell as in its first shell? 
17. Given below are some elements of the modern periodic table.
    ₄Be ₉Fe ₄Si ₁₉k ₂₀Ca
    (i)Select the element that has one electron in the outermost shell and write its electronic configuration.
    (ii)Select two elements that belong to the same group. Give reasons for your answer.
    (iii) Select two elements that belong to the same period. Which one of the two has a bigger atomic size?
18. The electrons in the atoms of four elements A B C D are distributed in three shells having 1,3,5 and 7 electrons in the outermost shell respectively.
    State the period in which these elements can be placed in the modern periodic table. Write the electronic configuration of the atoms of A and D and the molecular formula of the compound formed when A and D combined.
19. What is a periodic table? How many groups and periods does the modern periodic table have?
20. What are alkali ad alkaline earth metals?
21. Define periodicity.
22. Define Valency.
23. Name two elements in each case.
    (a) Alkali metal 
    (b) Alkaline earth metal
    (c) Halogen 
    (d) Inert gas
    (e) Transition elements 
24. Name two elements that have the same chemical properties to calcium.
25. An element has 2 electrons in its N shell.
    (a) What is its atomic number?
    (b) State its position in the periodic table.
    (c) Is it metal or non-metal?
    (d) State the name of this group.
26. Element A has atomic number 14. To which period does this element belong and how many elements are there in this period?
27. Answer the following questions in respect of elements  31P15
    (a) Give its electronic configuration 
    (b) To which group and period do it belong?
    (c) What is its Valency?
    (d) Is it metal or non-metal?
    (e) Is it reducing agents or oxidizing agents?
    (f) Give its formula with chlorine. 
28. Give the trends in atomic size on moving :
    (a) Down the group
    (b) Across the period right to left.
29. Which is greater in size?
    (a) An atom or a cation
    (b) An atom or anion
    (c) Fe2+  or  Fe3+
30. Chlorine, fluorine, and bromine are kept in the same group on the basis of similar properties. 
    (a) What are those similar properties?
    (b) What is the common name of this group? 
31. How do the following change in moving from left to right in a periodic table?
    (a) Atomic structure 
    (b) Chemical reactivity
32. How does the chemical reactivity of 
    (a) Alkali metals vary?
    (b) Halogen vary?
33. An element X belongs to the 3rd period and group II of the periodic table. State.
    (a) The number of valence electrons,
    (b) The Valency,
    (c) Name of the element,
    (d) Whether it is a metal or nonmetal.
34. From the following part of the periodic table, answer the following questions:
    (i) Which is the most reactive metal?
    (ii) Name the family of fluorine Q, R, and T.
    (iii) Name one element which of group 2 and 15.
    (iv) Give the name of the element P placed below carbon.
    (v) Compare X and P with respect to the size of atoms.

    1 Lithium	2	13	14 Carbon	15	16 Oxygen	17 Fluorine
    X			P			Q
    Y						R
    Z						T

Chapter 1 - Chemical Reactions and  Equations	Quick View	Questions with Solutions
Chapter 2 - Acid, Bases and Salt	Quick View	Questions with Solutions
Chapter 3 - Metal and Non-metals	Quick View	Questions with Solutions
Chapter 4 - Carbon and it's compound	Quick View	Questions with Solutions
Chapter 5 - Periodic Classification of Elements	Quick View	Questions with Solutions
Chapter 6 - Life Processes	Quick View	Questions with Solutions
Chapter 7 - Control and Co-ordination	Quick View	Questions with Solutions
Chapter 8 - How do Organisms Reproduce?	Quick View	Questions with Solutions
Chapter 9 -  Health and Heredity	Quick View
Chapter 10 -  Reflection and Refraction	Quick View	Questions with Solutions
Chapter 11 -  Human Eye Colourful World	Quick View	Questions with Solutions
Chapter 12 -  Electricity	Quick View	Questions with Solutions
Chapter 13 -  Magnetic Effect of Electric Current	Quick View	Questions with Solutions
Chapter 14 -  Sources of Energy	Quick View
Chapter 15  - Our Environment	Quick View
Chapter 16 - Management of  Natural  Resources	Quick View