With reference to the impact of oils and fats on the environment, consider the following statements: 1. In pipes, they can harden and cause blockages. 2. In open drains, they significantly increase the soil's porosity and filtration capacity. Which of the statements given above is/are correct?

Correct Option The correct option is (a). Explanation The improper disposal of cooking oils and fats, often collectively referred to as FOG (Fats, Oils, and Grease), poses significant challenges to both sewage infrastructure and environmental health. Their physical properties change with temperature, leading to detrimental effects on drainage systems and soil characteristics. Statement-wise Analysis - Statement 1 is Correct: Oils and fats are typically liquid when hot but solidify as they cool down. When poured into sinks or pipes, they harden and accumulate on the inner walls of the drainage infrastructure. Over time, this accumulation restricts the diameter of the pipe, leading to severe blockages. In municipal sewage systems, these deposits can combine with non-biodegradable solids to form massive obstructions known as "fatbergs." - Statement 2 is Incorrect: When oils and fats are released into open drains or directly onto the ground, they coat soil particles and fill the voids (pores) between them. This process clogs the soil pores, thereby reducing (not increasing) the soil's porosity and water filtration capacity. Consequently, this hinders the percolation of water into the ground and can prevent effective groundwater recharge. Key Takeaway: Oils and fats should not be disposed of in drains because they harden to cause pipe blockages and clog soil pores, significantly reducing soil porosity and water absorption capacity.

With reference to the impact… - NCERT Class 7 Environment & Ecology MCQ

NCERT Class 7 Environment & Ecology — Chapter 2: Wastewater story

mcqmedium

With reference to the impact of oils and fats on the environment, consider the following statements:

In pipes, they can harden and cause blockages.
In open drains, they significantly increase the soil's porosity and filtration capacity.

Which of the statements given above is/are correct?

NCERT textbook question

From NCERT Science - class 7 · Page 161

Options

A1 only
B2 only
CBoth 1 and 2
DNeither 1 nor 2

Did you get this right?

Solution

Correct Option

The correct option is (a).

Explanation

The improper disposal of cooking oils and fats, often collectively referred to as FOG (Fats, Oils, and Grease), poses significant challenges to both sewage infrastructure and environmental health. Their physical properties change with temperature, leading to detrimental effects on drainage systems and soil characteristics.

Statement-wise Analysis

Statement 1 is Correct: Oils and fats are typically liquid when hot but solidify as they cool down. When poured into sinks or pipes, they harden and accumulate on the inner walls of the drainage infrastructure. Over time, this accumulation restricts the diameter of the pipe, leading to severe blockages. In municipal sewage systems, these deposits can combine with non-biodegradable solids to form massive obstructions known as "fatbergs."
Statement 2 is Incorrect: When oils and fats are released into open drains or directly onto the ground, they coat soil particles and fill the voids (pores) between them. This process clogs the soil pores, thereby reducing (not increasing) the soil's porosity and water filtration capacity. Consequently, this hinders the percolation of water into the ground and can prevent effective groundwater recharge.

Key Takeaway: Oils and fats should not be disposed of in drains because they harden to cause pipe blockages and clog soil pores, significantly reducing soil porosity and water absorption capacity.

Your note

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