To determine which of the statements are false, we will analyze each statement one by one.
### Step-by-Step Solution:
1. **Statement 1: "The word antibiotic is a misnomer."**
- The term "antibiotic" comes from the Greek word "anti," meaning "against," and "bio," meaning "life." In the context of antibiotics, they are substances that act against harmful bacteria (pathogens) and do not harm human cells. Therefore, the statement that antibiotics are "against life" is misleading, as they are specifically against disease-causing organisms. This statement is **true**.
**Hint:** Consider the context of the term "antibiotic" and what organisms it targets.
2. **Statement 2: "Flocs are masses of bacteria with interwoven fungal filaments forming mesh-like structures."**
- Flocs are indeed aggregates of bacteria and other microorganisms, including fungal filaments, that form a mesh-like structure. They are commonly used in wastewater treatment processes, where they help in the biological treatment of sewage. This statement is **true**.
**Hint:** Think about the role of flocs in biological treatment processes and their composition.
3. **Statement 3: "Components in biogas are carbon dioxide (CO2, 25-35%), hydrogen (H2, 1-5%), nitrogen (N2, 2-7%), and hydrogen sulfide (H2S, traces)."**
- Biogas primarily consists of methane (CH4), carbon dioxide (CO2), and small amounts of other gases like hydrogen sulfide (H2S). The percentages mentioned in the statement may vary, but the presence of these components is generally accurate. However, nitrogen is not a significant component of biogas. Therefore, this statement is **false**.
**Hint:** Recall the main components of biogas and their typical concentrations.
### Conclusion:
- The false statement among the three provided is **Statement 3**.
### Final Answer:
- The false statement is: **3. Components in biogas are carbon dioxide (CO2, 25-35%), hydrogen (H2, 1-5%), nitrogen (N2, 2-7%), and hydrogen sulfide (H2S, traces).**
