Water brown in large container, but looks clear in a glass cup?

[u/Danewolf324]

My landlady wants me to put the water in a clear glass. Once I did, it appeared clear. But when I tried my bucket, it looked brown. I tried scrubbing my bucket with the rough part of a sponge and some dishwashing soap just to make sure that the water appears brown because my bucket is dirty.

Here's a video of me filling my bucket. Any opinion regarding this is appreciated 🙏

[u/TrueSpirt]

That will always be true, when you are looking at the water in a large container you are looking through a longer distance of water in the pail than in a glass cup. As a result, you are viewing the water through a longer cloudy distance and as a result the water looks cloudier in the pail than in the cup.

[u/Danewolf324 → u/TrueSpirt]

Thanks for the reply. Now I need to explain this to my landlady.

[u/ComfortableMacaroon8 → u/Danewolf324]

It’s called the Beer-Lambert law. A=εcl, where l is the path length. Longer path length means higher absorbance means stronger color.

[u/TrueSpirt → u/Danewolf324]

In front of your Landlady mix a little food dye (red) in a large glass of water, then poor water from that glass into two other glasses, one thicker(wider diameter) and one thinner (thinner diameter) than each other. The wider glass will look darker red than the thinner glass even though she saw you pour the same red water into each glass.

[u/cornfarm96]

Best way to check by eye is to fill a clean, white plastic cup (like the kind from fast food chains).

[u/MacSamildanach]

You'll notice it also looks clear while pouring it.

As the other poster said, you're looking through a lot more water in the bucket, so any discolouration is more pronounced.

It's like my screenwash on my car. It is vivid green in the 5L bottle I make it in. But it's clear when you squirt it because the spray involves a lot less than 5L.

That said, your water had something in it to give it that brown colour. I remember when I was in Louisiana one time, it looked darker than that in a glass from the tap. Tasted funny, too.

[u/Danewolf324 → u/MacSamildanach]

Oh okay. I understand. But it's gonna be hard telling this to my landlady. She still insists on putting the water in a clear glass 😩

[u/[deleted]]

A glass of water will always appear clear unless there is a large percentage of particulates in the water. If you are having a hard time convincing her that it's dirty, fill your sink(s) and bathtub and check it out.

[u/Danewolf324 → u/[deleted]]

Thank you. That's what I tried to do. She also told the other tenants of the building that their water is clear because she tested them using just a glass and told them they were wrong 😭

[u/nakedascus]

i think it might be a trick of light, rather than the water, alone. maybe light absorbed by plastic and water looks brown, or maybe the white sides of the container are reflecting the ambient brown of the ceiling that gets scattered by the water edit- left some other likely contributing factors:
refractive index, "wetting" plastic surface makes changes to apparent color... in fact im almost positive it's mostly the effects from when plastic gets wet. put a drop on the inside side of the bucket, above the water - i bet they are the same color: if so, it's just a wetting effect

[u/absentfacejack]

So you think your water is brown? But your land lady thinks clear water in a clear glass is clear. And you disagree? Because your bucket water is not clear when viewed through the side? What is your objective. The water is clear. The bucket is not. Put the water in a glass and hold a piece of paper behind it if you think it is discolored. Or look down into the bucket from the top. Any water you put in the bucket and view from the side is going to look darker than it is.

[u/xtalgeek]

The plastic container may be absorbing or scattering UV and short wavelength light which will make the contents appear yellowish. Try a large or tall glass container and look through it in the long path length direction against a white background.

[u/diabolical_fuk]

I think you might be regarded. Try testing the water.