Ninth class chemistry mcqs (periodicity of elements)
Chapter 4 Periodicity of Elements“People are bad enough to tease you but I amsure you are good enough to forgive them”1. law of triads was proposed by: a) Doberinier b) Lother Mayer c) Newland d) Mendeleef2. Modern classification is based on atomic number. a) true b) false3. law of octaves was proposed by: a) Doberinier b) Lother Mayer c) Newland d) Mendeleef4. Mg being eighth element from Be has the similar properties with it. The statement comes from: a) law of octaves b) law of triads c) Lother Mayer’s classification d) Mendeelev’s periodic table5. atomic volume = ? a) gram atomic Weight * density b) gram atomic Weight / density c) gram atomic weight + density
d) gram atomic weight – density6. Mendeleev arranged the elements in order of increasing: a) atomic volume b) atomic mass c) atomic number d) periodicity7. Mendeleev’s periodic table was remarkable in having: a) columns b) rows c) both d) gaps for unknown elements8. Mendeleev’s periodic table failed to give the idea of atomic structure. a) true b) false9. regarding the periodic table the incorrect statement is: a) rows have similar properties b) it does not contain isotopes c) shows the periodicity of elements d) N.O.T10. Eka boran was later termed as: a) boron b) scandium c) gallium d) germanium11. …..proved atomic mass not as the fundamental property of elements: a) radioactivity b) isotopes c) electronic configurationd) periodicity
12. atomic number was discovered by: a) doberinier b) newland c) baquerel d) mosely13. the longest period is: a) first b) second c) sixth d) seventh14. the sixth period contains: a) 6 b) 8 c) 16 d) 3215. the elements of sub group A are called transition elements. a) true b) false16. group 1A and 2A contain alkali metals: a) true b) false17. the most stable of the following elements is: a) Na b) N2 c) Ni d) Ne18. the most reactive is: a) Na b) Mg c) Na+ d) F19. The valency of seventh A group is : a) +1 b)-1 c) +2 d)-220. boron is metalloid: a) true b) false.
21. it exists in tetameric form: a) K b) P c) N d) Sb22. inert or noble gases are placed in the group: a) 3A b) 4A c) 7A d) 8A23. electronegativity of fluorine is: a) 1 b) 2 c) 3 d) 424. the minimum energy required to remove an electron from an atom in gaseous state is called: a) electronegativity b) electron affinity c) ionization potential d) P.E25. 1Å = ? a)10-8 b) 10-9 c)10-7 d) 10-1026. atomic number depends upon the number of shells but does not depend upon the nuclear charge. a) true b) false27. the energy change that occurs when an electron is gained by an atom in gaseous state is called: a) electron affinity b) ionization potential c) enthalpy d) electronegativity
28. the relative tendency of an atom in a molecule to attract shared pair of electrons towards itself is called: a) electron affinity b) ionization potential c) enthalpy d) electronegativity29. electronegativity decreases down the group. a) true b) false30. the incomplete period is: a) first b) fourth c) sixth d) seventh31. which period contains only gases a) first b) fourth c) sixth d) seventh32. it is the radioactive element of 1A group. a) Li b) Rb c) Cs d) Fr33. the valency of alkaline earth metals is: a) +1 b) +2 c) -1 d) -234. N and P are non metals. a) true b) false35. which pair of elements is chemically similar: a) K, Cr b) Cu, Ca c) F, Cl d) N, O
ANS KEY1 A 2 A 3 C4 A 5 B 6 B7 D 8 A 9 A10 B 11 A 12 D13 C 14 D 15 B16 B 17 D 18 C19 B 20 A 21 B22 D 23 D 24 C25 A 26 B 27 A28 D 29 A 30 D31 A 32 D 33 B34 A 35 C