Question

Q.4 The main ingredients of Portland cement are/ पोर्टलैंड सीमेंट के मुख्य अवयव है 

1 Lime and Silica/ चूना और सिलिका

2 Silica and alumina/सिलिका और एलुमिना

3 Lime and alumina/चूना और एलुमिना

4 Fe.Al2O3 ​

Answer 1

Explanation:

The chief chemical components of portland cement are calcium, silica, alumina and iron. Calcium is derived from limestone, marl or chalk, while silica, alumina and iron come from the sands, clays and iron ore sources..