CBSE Class 11 Chemistry Classification of elements Assignment

Question. Correct order of ionisation potentials of B, C, Al, Si is : 
(A) B < Al < Si< C
(B) B < Si < Al < C
(C) Al < B < Si < C
(D) Al < Si < B < C
Answer. D

Question. Element “X” which is solid and having high melting point, form a Chloride “XCl₃”. This element “X” would be in which group of Periodic table ? 
(A) Na
(B) Mg
(C) Al
(D) Si
Answer. C

Question. Arrange the following elements in order of their increasing ionisation energies. O, S Se, Te, Po :
(A) Se, Te, S, Po, O
(B) O, S, Se, Te, Po
(C) Po, Te, Se, S, O
(D) Te, O, S, Po, Se
Answer. C

Question. Electron affinities of O, S, F and Cl are in the order :
(A) O < S < F < Cl
(B) S < O < Cl < F
(C) S < Cl < O < F
(D) S < O < F < Cl
Answer. A

Question. In periodic table generally following similarity is found in elements of same group.
(A) Atomic number
(B) Number of electrons in outermost orbit of an atom
(C) Number of isotopes
(D) Atomic volume
Answer. B

Question. The correct order of increasing acidic nature of SO₂, SiO₂, P₂O₃ and Al₂O₃ is-
(A) SO₂< P2O₃ < SiO₂ < Al₂O₃
(B) Al₂ O₃ < SiO₂ < SO₂ < P₂O₃
(C) Al₂ O₃ < SiO₂ < P2O₃ < SO₂
(D) SiO₂ < SO₂ < Al₂O₃ < P₂O₃
Answer. C

Question. Which one among the following is not a periodic property ? 
(A) Electronegativity
(B) Atomic volume
(C) Ionization potential
(D) Radioactivity
Answer. D

Question. In modern periodic table; arrange the third row elements Na, Mg, AI and Si in the increasing order of their atomic size: 
(A) Na > Mg > AI > Si
(B) AI > Si > Na > Mg
(C) Si > Al > Mg > Na
(D) Na > AI > Si > Mg
Answer. A

Question. Which of the following elements belong to Lanthanide series ? 
(A) Ce
(B) Hg
(C) Th
(D) Mn
Answer. A

Question. d-block elements are :
(A) Representative elements
(B) Transition elements
(C) Inner transition elements
(D) Inert gases
Answer. B

Question. On going from left to right in a period, the size of atom decreases but the size of the nobel gas atom is greater than the size of other elements of same period, why ? 
(A) Less reactivity
(B) Measurment of Vander Waals radius
(C) Absence of any valence electron
(D) Effective nuclear charge in greater
Answer. B

Question. Which of the following oxide of nitrogen is ionic? 
(A) NO
(B) N₂O₃
(C) N₂O₅
(D) NO₂
Answer. C

Question. Which of thefollowing group belongs to actinide series ? 
(A) Th, Pa, U
(B) Ce, Pr, Nd
(C) Ba, La, Hf
(D) Pt, Au, Ag
Answer. A

Question. Among LiCl, RbCl, BeCl₂ and MgCl₂ which two are the heighest and lowest ionic compounds ?
(A) LiCl & RbCl
(B) RbCl & BeCl₂
(C) RbCl & MgCl₂
(D) MgCl₂ & BeCl₂
Answer. A

Question. The bond, in compound formed from combination of 14 group and 17 group elements of Periodic table will be ............ 
(A) Electrovalent bond
(B) Co-ordinate bond
(C) Van der Waals bond
(D) Covalent bond
Answer. D

Question. Which of the following orders of atomic radii is correctly represented ?
(A) B < Al < Ga
(B) B < Ga ≈ Al
(C) Al < B < Ga
(D) B > Ga ≈ Al
Answer. B

Question. An element A belongs to third period and second group of periodic table. The number of valence electron / electrons of element A is
(A) one
(B) two
(C) three
(D) four
Answer. B

Question. Which pair of atomic numbers represents elements in same group ?
(A) 11, 19
(B) 6, 12
(C) 4, 16
(D) 8, 17
Answer. A

Question. Which of the following is considered to be an anomalous pair of elements in Mendeleev's periodic table based on atomic weights ?
(A) Na/K
(B) H/He
(C) Te/I
(D) Fe/Co
Answer. C

Question. Periodicity in the properties of elements in modern periodic table is due to :
(A) A regular increase in atomic weight of elements.
(B) Periodicity in the electronic configuration of atom of elements.
(C) Successive increase in the atomic number of elements.
(D) Existence of families of elements.
Answer. B

Question. X, Y and Z are the three elements, each one belongs to any one of the groups IA, IIIA and VA. The oxide of X is amphoteric, the oxide of Y is highly acidic, and the oxide of Z is highly basic. Identify the groups to which these elements X, Y, Z belong to ? 
      X     Y    Z
(A) VA  IA   IIIA
(B) IA   VA   IIIA
(C) IIIA  IA  VA
(D) IIIA  VA  IA
Answer. D

Question. The noble gas which occurs most abundantly in the atmosphere is : 
(A) He
(B) Ne
(C) Ar
(D) Kr
Answer. C

Question. Which of the following orders of ionic radii is correctly represented?
(A) H^–> H⁺> H
(B) Na⁺> F^–> O^2–
(C) F^–> Na⁺> O^2–
(D) H^–> H > H⁺
Answer. D

Question. Which of the following statement is incorrect statement about the trends when going from left to right across the periods of modern periodic table? 
(A) The number of valence electrons in creases
(B) The atoms lose their electrons more easily
(C) The oxides become more acidic
(D) The elements become less metallic in nature
Answer. B

Question. The correct order of acidic strength of the following oxides is : 
(A) CaO < Na₂O < CO₂ < ZnO
(B) Na₂O < CaO < ZnO < CO₂
(C) ZnO < CO₂ < CaO < Na₂O
(D) CO₂ < ZnO < Na₂O < CaO
Answer. C

Question. Which of the following compound can be decomposed in presence of sunlight.
(A) NaCl
(B) CuCl
(C) AgCl
(D) KCl
Answer. C

Question. An element X forms a solid chloride having formula XCl₂ The solid chloride has high melting point (m.p.). To which group of the periodic table will X belongs to : 
(A) I group
(B) II group
(C) XIII group
(D) XVI group
Answer. B

Question. Which one of the following is the smallest in size ? 
(A) N^3–
(B) O^2–
(C) F^–1
(D) Na⁺
Answer. D

Q1. Define
(I) Ionization Energy
(II) Electron gain affinity
(III) Electronegativity
(iv) Covalent Bond
(v) Octet rule
Q2. Write the factors that affects the ionization energy.
Q3. Explain Why n-shell contains maximum 18 electrons.
Q4. Write IUPAC name & symbol of 115,120,114,106.
Q5. Write the general electronic configuration of d & f block . write the properties of these blocks.
Q6. Give reason (I) the ionization enthalphy of nitrogen is more than oxygen
(ii) the first ionization of sodium is lower than magnesium but second ionization enthalphy of sodium is higher than magnesium.
Q7. How do atomic radii , electronegativity, electron gain enthalphy
Q8 What do you mean by isoelectronic molecule . Give two examples.
Q9 Out of F & CL Which one have more negative electron gain enthalphy & why
Q10 What would be the IInd electron gain enthalphy of oxygen as +ve, -ve, or less +ve . Justify your answer