All Questions
5
questions
3
votes
1
answer
201
views
Which component in my tap water "scale" does not react with acid?
Where I live we have pretty hard tap water and so I'm used to scale build-up in kettles and on bathroom tiles, easily removed with acids (it's mostly calcium carbonate I guess). However it seems a ...
- 131
1
vote
1
answer
820
views
When we add soap in low concentrations to water it reduces the surface tension. Why? What is the purpose of this?
I understand how soaps lower the surface tension of water but I don't know what the purpose of this is. How does this help with cleaning, removing stains etc?
- 318
4
votes
1
answer
330
views
How to clean glassware containing pesticide solutions
I have pesticide (dimethoate) dissolved in methanol in volumetric flasks and graduated cylinders. How do I clean this glassware properly before moving on to the next dilution of a different pesticide.
- 91
5
votes
2
answers
6k
views
Reuse 20 litre plastic drums for drinking water?
Would you consider it safe to clean and reuse a 20 litre plastic drum that contained 36% Hydrochloric Acid for drinking water? If so how would you recommend cleaning it?
- 51
12
votes
2
answers
5k
views
Soap and rain water, why does it not rinse off?
I am in Papua New Guinea at the moment, where rain water harvesting is the most common way of getting water.
When washing hands, the soap feels hard to rinse off, and my skin feels "greasy".
I read ...
- 221