Cement, the important building material is a mixture of oxides of several elements. Besides calcium, iron and sulphur, oxides of elements of which of the group (s) are present in the mixture ?

Options

A. Group 2
B. Groups 2, 13 and 14
C. Groups 2 and 13
D. Groups 2 and 14

Answer

B

Explanation

Cement is a product obtained by combining a material rich in lime. CaO with other material like clay which contains silica `SiO_(2)` alongwith the oxides of aluminium, iron and magnesium. The average composition of Portland cement is
`CaO(50-60%)`
`SiO_(2)(20-25%)`
`Al_(2)O_(3)(5-10%)`
`Fe_(2)O_(3)(1-2%)`
`SO_(2)(1-2%)`
`MgO(2-3%)`
Thus, it contains elements of group 2 (Ca), group 13 (Al) and group 14 (Si).