Soil Worksheet-6

Soil Worksheet-6

Multiple-Choice Question:

51. Which of the following minerals found in a granite is not altered by chemical weathering?

(A) feldspar         (B) quartz            (C) biotite            (D) magnetite

52. The physical and chemical weathering of granite will produce:

(A) mineral fragments and granite fragments          

(B) clay minerals and iron oxides

(C) ions dissolved in rainwater and soil water

(D) all of these

53. What is the term geologists’ use for the layer of loose, heterogeneous weathered material lying on top of the bedrock?

(A) laterite           (B) regolith (C) soil                 (D) humus

54. Carbonic acid, the primary agent of chemical weathering is produced by:

(A) plant roots             

(B) bacteria that feed on plant and animal remains

(C) carbon dioxide dissolving in rainwater

(D) all of these

55. Which of the following statements about weathering is false?

(A) the presence of soil slows down the weathering of the underlying bedrock

(B)  rocks of different compositions weather at different rates

(C)  the longer a rock is exposed at the surface, the more weathered it becomes

(D) heat and heavy rainfall increase the rate of chemical weathering

56. The usual vertical sequence of horizons in a soil from the upper surface to the lower one is:

(A) O, A, C, B, R                                (B) O, A, B, C, R            

(C) A, O, B, R, C                                (D) A, B, C, O, R

57. The amount of soil is _______ times more than that in the atmosphere.

(A) Ten times as much                    (B) Half               

(C) One third                                    (D) Twice as much

58. Which of the following is the best soil texture in terms of water availability for plants?

(A) sandy soils                                 (B) clay soils                 

(C) loamy soils                                 (D) silt soils

59. Which of the following layer is soft, porous, and can hold water?

(A) Topsoil                                       (B) Organic layer         

(C) Bedrock                                      (D) Parent material

60. Which of the following layer is rich in organic matter?

(A) Topsoil                                        (B) Organic layer

(C) Bedrock                                       (D) Parent material

Answer Key:

51. (B)
52. (D)
53. (B)
54. (D)
55. (A)
56. (B)
57. (D)
58. (C)
59. (A)
60. (B)