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Dr David Mills

The density of normal (pure) water is 1g / ml.
Heavy water is 1.12g / ml.

Let's check it. #Science

13 August at 9:08 | Open on mastodon.social
21 comments
Dr David Mills
🇮🇲Dan

@Dtl Whoa. That's some resolution!

13 August at 9:13 | Open on mstdn.social
Dr David Mills

This should be 6uL of pure 18 MOhm water. I suspect my pipette is slightly out of calibration.
This should read 6 mg. #science
13 August at 9:13 | Open on mastodon.social
Dr David Mills

Now with 6uL of heavy water.
It's heavier!
5.3791mg #science
13 August at 9:14 | Open on mastodon.social
Andrew Zonenberg

@Dtl Relative density of 1.124? I'm gonna say your heavy water is still pretty pure.

13 August at 9:17 | Open on ioc.exchange
Dr David Mills

@azonenberg I'm impressed it came out so well, I had expected this to be contaminated with light water.

13 August at 9:21 | Open on mastodon.social
Dr David Mills

I did a couple of other measurements of each of these, they came out the same to 2 decimal places. Must get the pipette calibrated again.

Running the numbers we get

5.38 / 4.78 = 1.125

Or near as dammit 1.12 for the density of this heavy water. If it had absorbed much normal water it would be less dense, so I can assume that within the limits of a 10 min experiment on a Tuesday morning before my second cup of Tea, that this heavy water is pretty pure.

#science

13 August at 9:18 | Open on mastodon.social
Ben Hardill

@Dtl it's definitely going to make for an interesting 2nd cup of Tea.

Does it impact the taste like hard/soft water?

13 August at 10:00 | Open on bluetoot.hardill.me.uk
Dr David Mills

@ben Wikipedia claims it tastes slightly sweet.

13 August at 10:16 | Open on mastodon.social
Allen Very Serious Versfeld

@Dtl How do you measure such tiny volumes? We got to use pipettes a little in high school chemistry but microliters? That's so small, I'd imagine that surface tension would keep trying to pull your sample back into the container? Is that a thing?

13 August at 9:21 | Open on mastodon.monoceros.co.za
Dr David Mills

@uastronomer It's a disposable tip quite hydrophobic and we push the liquid out with a small amount of air.

13 August at 9:22 | Open on mastodon.social
Christine Burns MBE 🏳️‍⚧️📚⧖

@Dtl Silly question maybe but how are you ensuring that your samples (and presumably the pipette) are at 20 degrees C?

13 August at 9:19 | Open on mastodon.green
Dr David Mills

@christineburns I'm not - the lab was definitely warmer than that, but everything was at the same temperature, so relative differences should be the same.

13 August at 9:20 | Open on mastodon.social
labria

@Dtl daaaam that’s a precise balance!

13 August at 9:22 | Open on social.yeschenko.com
labria

@Dtl it’s funny, the word “balance” doesn’t stick with this device for me, even though I used an actual balance to weigh things in Uni, with those tiiiny pieces of foil.

13 August at 9:28 | Open on social.yeschenko.com
Dr David Mills

@labria I know - it doesn't seem right at all for this equipment, but it's the name for it.

13 August at 9:53 | Open on mastodon.social
labria

@Dtl well, yeah. The only other option is to call most of those either volt or ampermeters :)

13 August at 12:25 | Open on social.yeschenko.com
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