The element which can form an acidic oxide should be the one whose atomic number is:

Which of the following are the correct characteristics of isotopes of an element?

(i) same atomic mass

(ii) same atomic number

(iii) same physical properties

(iv) same chemical properties

The correct formula of the oxide of Eka-aluminium element predicted by Mendeleev was:

The element which forms a basic oxide has the atomic number of:

Which one of the following does not increase while moving down the group of the periodic table?