Hazardous waste is liquid or solid that contains substances known to be A. Fatal to humans or animals only at high doses B. Toxic, carcinogenic or mutagenic to humans C. Ignitable even at temperatures less than 60°C D. Non-reactive E. Corrosive Choose the most appropriate answer from the options given below:
B, C and E Only
Understanding Hazardous Waste Characteristics
Hazardous waste is defined by its properties that make it dangerous or potentially harmful to human health or the environment when improperly managed. These properties are often categorized based on the risks they pose.
Analyzing Hazardous Waste Properties
Let's examine each statement provided in the question to determine which characteristics are associated with hazardous waste:
- Statement A: Fatal to humans or animals only at high doses.
This statement is too limiting. While some hazardous substances are fatal, the definition of toxicity for hazardous waste includes substances that can cause serious illness, reproductive effects, birth defects, or other harmful health effects, not just fatality, and not necessarily only at high doses. Many toxic effects occur at low exposures.
- Statement B: Toxic, carcinogenic or mutagenic to humans.
This statement accurately describes key characteristics of hazardous waste. Toxicity is a primary concern. Substances that are carcinogenic (cause cancer) or mutagenic (cause genetic mutations) are considered highly dangerous and are included in the definition of hazardous waste.
- Statement C: Ignitable even at temperatures less than $60^{\circ}C$.
Ignitability is a standard characteristic of hazardous waste. Wastes that can easily catch fire are dangerous due to the risk of combustion and potential explosions. A flashpoint below $60^{\circ}C$ is a common threshold for classifying liquids as ignitable hazardous waste.
- Statement D: Non-reactive.
This statement is incorrect. Reactivity is another defining characteristic of hazardous waste. Reactive wastes are unstable under normal conditions and can cause explosions, undergo violent changes, react with water, or release toxic gases. A non-reactive substance would generally not be classified as hazardous based on reactivity.
- Statement E: Corrosive.
Corrosivity is a key characteristic of hazardous waste. Corrosive substances, such as strong acids or bases, can damage materials and living tissue upon contact. Liquids with extreme pH values are typically classified as corrosive hazardous waste.
Identifying Characteristics of Hazardous Waste
Based on the analysis, the characteristics that define hazardous waste among the given options are:
- B. Toxic, carcinogenic or mutagenic to humans.
- C. Ignitable even at temperatures less than $60^{\circ}C$.
- E. Corrosive.
Statements A and D do not correctly describe the general properties used to classify hazardous waste.
Evaluating the Options
We need to find the option that includes only the correct statements (B, C, and E):
| Option | Statements Included | Correctness |
|---|---|---|
| 1 | A, C and D Only | Incorrect (A and D are not defining characteristics) |
| 2 | B, C and E Only | Correct (B, C, and E are defining characteristics) |
| 3 | B, C and D Only | Incorrect (D is not a defining characteristic) |
| 4 | C, D and E Only | Incorrect (D is not a defining characteristic) |
Therefore, the most appropriate answer is the one that includes B, C, and E only.
Revision Table: Hazardous Waste Properties
| Characteristic | Description |
|---|---|
| Toxicity | Causes harm to human health or the environment through ingestion, inhalation, or absorption. Includes substances that are toxic, carcinogenic, mutagenic, or teratogenic. |
| Ignitability | Can easily catch fire or cause a fire. Includes liquids with low flash points, solids that ignite readily, ignitable compressed gases, and oxidizers. |
| Corrosivity | Can corrode metal containers or cause severe damage to skin tissue. Typically defined by extreme pH values (very acidic or very alkaline). |
| Reactivity | Unstable under normal conditions and can explode, react violently, or produce toxic fumes when mixed with water or under other conditions. |
Additional Information on Hazardous Waste Identification
Regulatory bodies, such as the Environmental Protection Agency (EPA) in the United States, define hazardous waste based on these characteristics (Ignitability, Corrosivity, Reactivity, Toxicity - often referred to as the "RCRA characteristics"). Waste can also be listed as hazardous if it is specifically identified on regulatory lists due to containing certain known hazardous chemicals. Proper identification and management of hazardous waste are crucial to prevent environmental contamination and protect public health. Disposal methods for hazardous waste must be carefully controlled and regulated, often involving specialized landfills, incineration, or treatment processes to neutralize or stabilize the waste.
Important Questions from Miscellaneous
A stone is thrown horizontally from the top of a 20 m high building with a speed of 12 m/s. It hits the ground at a distance R from the building. Taking g = 10 m/s2 and neglecting air resistance will give :
A sphere of volume V is made of a material with lower density than water. While on Earth, it floats on water with its volume f1V (f1 < 1) submerged. On the other hand, on a spaceship accelerating with acceleration a < g (g is the acceleration due to gravity on Earth) in outer space, its submerged volume in water is f2V. Then:
A railway wagon (open at the top) of mass M1 is moving with speed v1 along a straight track. As a result of rain, after some time it gets partially filled with water so that the mass of the wagon becomes M2 and speed becomes v2. Taking the rain to be falling vertically and the water stationery inside the wagon, the relation between the two speeds v1 and v2 is :
Consider the following statements:
1. Distance between the longitudes becomes zero on North Pole and South Pole.
2. Distance between the longitudes is maximum on the Equator.
3. Number of longitudes is more than number of latitudes.
Which of the statements given above is/are correct?
One block of 2⋅0 kg mass is placed on top of another block of 3⋅0 kg mass. The coefficient of static friction between the two blocks is 0⋅2. The bottom block is pulled with a horizontal force F such that both the blocks move together without slipping. Taking acceleration due to gravity as 10 m/s2, the maximum value of the frictional force is :
