The operation of removal of impurities or clay adhering to iron ores, is known as ______

roasting

smelting

calcination

dressing

Correct Answer : dressing

Recently Updated in Building Materials Questions

The proportions of charcoal, saltpetre and sulphur in gun powder by weight, are respectively :

75, 10, 15

10, 15, 75

15, 75, 10

10, 75, 15.

Correct Answer : Option (C) : 15, 75, 10

A 1st class brick immersed in water for 24 hours, should not absorb water (by weight) more than ____

10%

15%

20%

25%

Correct Answer : Option (C) : 20%

According to IS 399-1963, the weight of the timber is specified at ______

12% moisture content

14% moisture content

8% moisture content

10% moisture content

Correct Answer : Option (A) : 12% moisture content