In good quality cement ratio of lime total oxides of Si(SiO\(_2\)), Aluminium(Al\(_2\)O\(_3\)) and Iron(Fe\(_2\)O\(_3\)) should be as close as possible to _____ .
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For high-quality cement, the lime to oxide ratio must be within the range of 1.9–2.1, ensuring good binding properties and durability
Correct Answer: 2
Solution and Explanation
Assessment of Cement Quality:
The quality of cement is assessed based on the ratio of lime (CaO) to the sum of oxides (SiO2, Al2O3, and Fe2O3). The formula for this ratio is:
Ratio = \(\frac{\% \text{CaO}}{\% \text{SiO}_2 + \% \text{Al}_2\text{O}_3 + \% \text{Fe}_2\text{O}_3}\)
For good quality cement, this ratio lies in the range of 1.9 to 2.1, which ensures the proper strength and binding properties of the cement. If the ratio deviates significantly:
- Higher ratio: May make the cement weak in resistance to environmental effects.
- Lower ratio: May reduce the binding efficiency and durability of the cement.
Conclusion: Since the ratio is closest to 2, the correct answer is 2.
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