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

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

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

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

On moving from left to right in a period of the periodic table, the atomic number of elements increases. What happens to the size of atoms of elements on moving from left to right in a period?