Question

The average composition of Portland cement is.

• A. CaO : 40 – 50%, $SiO_{2}$: 30 – 40% , $Al_{2}O_{3},$ $Fe_{2}O_{3}:$ 10 – 20%
• B. CaO : 50 – 60%, $SiO_{2}:$ 20 – 25%, $Al_{2}O_{3}$ : 5 -10% MgO : 2 – 3%, $Fe_{2}O_{3}$ : 1 – 2% and $SO_{3}:$ 1 – 2%
• C. $SiO_{2}:40 - 50\%,CaO:30 - 40\%,Al_{2}O_{3}:10 - 20\%$
• D. $CaO:50\%,SiO_{2}:50\%$

Answer 1

Answer: (B)

CaO : 50 – 60%, $SiO_{2}:$ 20 – 25%, $Al_{2}O_{3}$ : 5 -10%

MgO : 2 – 3%, $Fe_{2}O_{3}$ : 1 – 2% and $SO_{3}:$ 1 – 2%

Answer 2

: CaO: 50 – 60%, $SiO_{2}:20 - 25\%,Al_{2}O_{3};5 - 10\%$

MgO: $2 - 3\% Fe_{2}O_{3}:1 - 2\%$ and $SO_{3}:1 - 2\%$