Which of the following cleansing agents contain(s) alkalis?(I)Drain cleaners (II)Toilet cleaners (III)Glass cleaners

To address the question regarding which cleansing agents contain alkalis, let's analyze the options provided one by one.

1. Drain Cleaners:

   • Most drain cleaners, especially those that are caustic, contain alkalis like sodium hydroxide (lye) or potassium hydroxide. These substances help in breaking down organic materials that may be clogging the drain.

2. Toilet Cleaners:

   • Toilet cleaners can vary greatly in formulation; some alkaline-based toilet cleaners contain substances such as sodium hypochlorite or sodium carbonate, which are considered alkalis. However, not all toilet cleaners are alkaline; some may be acidic.

3. Glass Cleaners:

   • Glass cleaners are typically designed to be neutral or slightly alkaline, using compounds like ammonia, but they may not necessarily contain strong alkalis like those found in drain cleaners.

Final Conclusion

Based on the analysis:

• (I) Drain cleaners: Yes, they generally contain alkalis.
• (II) Toilet cleaners: Not always, but some can contain alkalis.
• (III) Glass cleaners: Generally do not contain strong alkalis.

Therefore, the answer is that Drain Cleaners (I) mostly contain alkalis.