Question

A number of elements are available on this Earth’s crust but most abundant elements are _____________.
A) Al and Fe
B) Fe and Cu
C) Cu and Ag
D) None of these

Answer 1

Hint:
Those elements that are major components of most of the minerals are the most abundant elements of this Earth’s crust. The Earth is 71% water and 29% land and in both oxygen is common because the soil, be it clayey or sandy must have minerals formed from oxides and less likely, sulphides and metals.

Complete step by step solution:
99% of the Earth’s Crust is made up of just eight elements and occurs mainly in the combined state. Minerals are elements that occur naturally in the earth’s crust. The major component of most of the minerals is ‘oxygen’ where the percentage of this element is 47%, which means that 47% of the earth’s crust is occupied by oxygen. This is followed by ‘silicon’ which occupies 28% of the earth’s crust as silica is a part of most of the minerals. These elements are followed by Aluminium (8%), Iron (5%), Calcium ($3.5\% $), Sodium (3%), Potassium ($2.5\% $), Magnesium (2%), and all other remaining elements 1%. Among the given options, it can be seen that aluminium and iron are the most abundant elements.

Hence the answer to the above question option A, Al and Fe.

Note:
Silicate minerals like Basalt, granite, gneiss, schist, sandstone, etc. are the most common type of rock forms that build up the earth’s surface. These are followed by the carbonate minerals like limestone and dolomite, and evaporates like gypsum and rock salt.