Which element was not known when Mendeleev proposed his classification ?

Related Mcqs:

1. Which discovery caused a revision in the periodic law as stated by Mendeleev ?

   A. Location of nucleus by Rutherford
   B. Atomic number by Moseley
   C. X-rays by Roentgen
   D. Natural radioactivity by Henry Bacquerel.

2. Many properties of an element and its compounds can be predicted from the position of the element in the periodic table. What property could not be predicted in this way ?

   A. The nature of its oxides
   B. The charge on its ions
   C. The formula of its oxide
   D. Its number of isotopes

3. Which of the following way in used for classification of chromatography ?

   A. Shape
   B. Phase
   C. Mechanism
   D. All

4. An element has electronic conviguration 1s2 2s2 2p2. It belongs to__________________?

   A. Group II-A
   B. Group IV-A
   C. Group VII-A
   D. Group VI-A

5. The atoms of same element having same atomic number but different mass number are called____________________?

   A. Isobars
   B. Isomers
   C. Isotopes
   D. Isotropes

6. Which one of the following element has highest oxidation state in its compounds ?

   A. Cr
   B. Mn
   C. Sn
   D. O

7. An element having low value of ionization energy and low value of electron affinity is likely to belong to__________________?

   A. Group IA
   B. Group IB
   C. Group VIIA
   D. Group VIII

8. Halides in which halogen atoms act as a bridge between two atoms of the other element are called___________________?

   A. Covalent halides
   B. Electronegative halides
   C. Polymeric halides
   D. Polymeric hydrides

9. Law of mass action was proposed by Goldberg and Peter Waage in _________?

   A. 1864
   B. 1866
   C. 1888
   D. None of These

   Submitted by: Name

10. The strength of solution of an element whose electrode potential is to be measured is________________?

    A. 2M
    B. 1N
    C. 1m
    D. 1M