Question

Four samples of the same material with identical composition and mass were cut as shown in the diagrams below.

When subjected to the same chemical weathering,which sample will weather at the fastest rate?

1) A
2) B
3) C
4) D

Answer 1

Answer:

D

Explanation:

Sample D will undergo the fastest rate when subjected to chemical weathering.

What is weathering?

• It is the physical disintegration and chemical decomposition of rocks to form sediments and soils.
• Physical weathering is also known as mechanical weathering. It entails breaking rocks into smaller sized chunks.
• Chemical weathering is the decomposition of rocks by chemical action.

From the given choices, option D will have the largest surface area exposed to chemical actions. It has more surface area compared to the others. The more broken a mass is, the more its surface area is.

Reaction rates are affected by:

• Increase in surface area
• Increase in temperature
• Higher concentration
• Increase in pressure

The last cube has the highest surface area and will have the fastest rate of weathering.