Wikipedia:Reference desk/Archives/Science/2018 February 3

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February 3

Cat claws in a fight

Do cats use their claws to scratch each other when fighting? I haven't seen such instances. Thanks. 77.254.12.184 (talk) 15:31, 3 February 2018 (UTC)

Are Your Cats Playing Or Fighting?. Alansplodge (talk) 15:52, 3 February 2018 (UTC)

This suggests they do, and as they use their claws very freely on humans when they try to restrain them I can't think of a good reason why they wouldn't. I've certainly seen a cat using it claws on a dog that brought into our house - the poor dog wondered what hit it when she clung to his face for a few seconds scratching it with her back claws and then disappeared. After a real cat fight they often end up with bits of fur and ears missing, I'm sure no animal would allow that to happen without using all the weapons at its disposal. Richerman (talk) 22:28, 3 February 2018 (UTC)

For what little it's worth: I've known many cats, but only one who used his claws during play. He was a bony kitten when we found him and I suspect that he was separated too early from his siblings, else they'd have taught him courtesy. –Tamfang (talk) 02:37, 4 February 2018 (UTC)

Kittens learn to control their claws very fast - in their first month. Cats have a natural urge to sharpen/use their claws so they have plenty of training and full control when they are grown up. Then its simply a question of character and their local cat society's Code of conduct. Normal housecats are likely rather peaceful. My aunt once had a cat she claimed grew up wild, which always seem very serious, unforgiving and unapproachable. Since i used to play with every cat i encountered (i just love them) i got some very painful lessons from my aunt's cat for not waiting for an explicit invitation. So cats use their claws very flexible, as they see fit. --Kharon (talk) 05:43, 4 February 2018 (UTC)

They certainly use their hind claws when fighting (or when play gets out of hand). Matt Deres (talk) 15:11, 4 February 2018 (UTC)

Concentrated Sodium cloride

I take table salt, drop it in a glass full of water and stir carefully. I wait until the excess of salt settles to the bottom. Now there is equilibrium. What is the concentration of sodium chloride in the water above the sediment? Thanks, - AboutFace 22 (talk) 21:58, 3 February 2018 (UTC)

It depends on the temperature of the water see Solubility table but at room temperature it should be somewhere between 35% and 36% assuming it's pure salt, however, table salt may be fortified or may contain anti-caking agents. Richerman (talk) 22:16, 3 February 2018 (UTC)

• The Solubility table lists grams of sodium chloride per 100 ml of water, with results between 35 and 38 depending on temperature. I don't know how to express this as a percentage or if there is some different formal way to express a concentration. -Arch dude (talk) 01:23, 4 February 2018 (UTC)

3.5 to 3.8%, or 5.6 to 6.5 molar. Fgf10 (talk) 09:30, 4 February 2018 (UTC)

Er, surely you mean 35% to 38%? It's dissolved in 100ml not 1,000ml. Richerman (talk) 22:46, 4 February 2018 (UTC)

@Richerman & @Arch dude, thank you. AboutFace 22 (talk) 01:32, 4 February 2018 (UTC)

Environmental science question.

How much food in kg does the average human adult need to eat to give the dunny a good filling at least twice a day?149.254.234.82 (talk) 22:58, 3 February 2018 (UTC)

(Dunny: Australian slang for outhouse.) Looie496 (talk) 23:13, 3 February 2018 (UTC)

Well actually no, it's Australian slang for a shithouse. Richerman (talk) 23:53, 3 February 2018 (UTC)

Depends how much Dietary fiber or Prebiotic (nutrition) your food contains. If your Defecation happens three times in one day you likely have Diarrhea. I am not a medical expert but i doubt defecting twice a day is regarded normal. I also doubt you can enforce defecation that far by eating as much food as you can manage. --Kharon (talk) 05:21, 4 February 2018 (UTC)

Defacation twice a day is perfectly normal (just Google it) for me, and I certainly don't overeat.--Shantavira|^{feed me} 09:18, 4 February 2018 (UTC)

Oh, one can easily force defecation to twice a day by overeating. Abductive (reasoning) 07:39, 4 February 2018 (UTC)

Maybe not the greatest source but this [1] from one of the UK's NHS says "It is normal to open your bowels from between three times a day to three times a week". Nil Einne (talk) 09:44, 5 February 2018 (UTC)

WHAAOE: In making my contributions to the Outhouse, I discovered more than expected about Dunny. Carbon Caryatid (talk) 13:58, 4 February 2018 (UTC)

• When I was a child I shate as a child; once upon waking and once after dinner. Now I peer through the rim darkly, as I await the last passing, and eat figs. μηδείς (talk) 02:22, 6 February 2018 (UTC)