1671: Urea is prepared by the chemical reaction of:
(a) Ammonia and Carbon dioxide
(b) Ammonium sulphate and calcium chloride
(c) Acetamide and ethyl alcohol
(d) Chlorine and water
1672: Trade winds are caused by the:
(a) Revolution of the earth
(b) Rotation of the earth
(c) In flowing movement of air along the earth's surface towards the equator
(d) None of the above
1673: Consider the following pairs: Region often Country in news
1. Chechnya : Russian Federation
2. Darfur : Mali
3. Swat Valley : Iraq
Which of the above pairs is / are correctly matched ?
(a) 1 only
(b) 2 and 3 only
(c) 1 and 3 only
(d) 1, 2 and 3
1674: Isohyets are the lines drawn on a map connecting points having:
(a) Equal temperature
(b) Equal height
(c) Equal atmospheric pressure
(d) Equal rainfall
1675: Assertion (A):
Coal-based thermal power stations contribute to acid-rain.
Reason (R):
Oxides of carbon are emitted when the coal burns.
(a) Both A and R are individually true and R is the correct explanation of A
(b) Both A and R are individually true but R is NOT the correct explanation of A
(c) A is true but R is false
(d) A is false but R is true