Benedict's Reagent

In this video I synthesize and demonstrate Benedict's reagent, which is a chemical reagent commonly used to test for the presence of reducing sugars in qualitative analysis. I may also eventually make the quantitative form, but I haven't decided yet.
#chemistry #science #hydrogen #gas #elements #fire #chemical #industury #color #light #poison #orange

[@aqua-op]

Did you ask benedict if you could play with his reagent first?

[@jogandsp]

Its really nice to find another chemistry UA-camr doing real chemistry with real explanations instead of just doing the same click bait crap that most "science" UA-camrs do

[@experimental_chemistry]

Benedict's reagent has many advantages over Fehling's solution: even when mixed, it has a longer shelf life, it is less corrosive and therefore more suitable for student experiments.
I only know the qualitative use and would be very curious about the quantitative one.
In fact, the mixture must contain enough citrate and carbonate: too little citrate and copper carbonate precipitates, too little carbonate and copper citrate precipitates (which is also an interesting chemical).
When neutralizing the citric acid, I recommend adding washing soda instead of baking soda right from the start: it is cheaper, you only need half the molar amount and it is necessary as a third component anyway.
To test for lactose, the milk protein should first be separated as casein by adding acetic acid and the filtrate should then be boiled and filtered again. Otherwise - as you can see here - the Biuret reaction occurs, which disrupts the effect of the Benedict reagent.
The Wöhlk test is more suitable for detecting lactose or maltose because it is more specific.
Btw: 0:50 copper sulfate forms a pentahydrate, not a tetrahydrate...

[@jschlo6767]

@0:48 The CuSO4 is pentahydrate, not tetrahydrate :)

[@integral_chemistry]

Oof 😅 yeah good catch! My bad on that

[@R-Tex.]

This was my first chemistry experiment ever. Our great teacher let us perform this back in 6th grade!

[@kevinmarrs3372]

Correction @5:35
Aldehyde group not carboxylic acid

[@integral_chemistry]

yeah my bad on that. I tried to make a in-text correction to that because I didn't feel like going back and re-recording lol

[@NiC.kChenNC]

This is awesome

[@LFTRnow]

Very good demo!
Acids such as lemon juice or cream of tartar cause sucrose to break up (or invert) into its two simpler components, fructose and glucose. How about trying the sucrose again but add some acid to break it up? Could try that on the milk as well. I'd suggest using skim milk so you don't have to deal with the fat.

[@XemplarSoft]

Could you make your own test strips like this?

[@TechGorilla1987]

You and Nurd Rage drop a video at the same time - choice. Science Saturday.

[@experimental_chemistry]

... and Tommy Technetium, Amateur Chemistry, Chemiolis etc.

[@jacobyoung7018]

I thought that the decahydrate of sodium carbonate wasn't stable at stp, isn't it commonly found as the monohydrate?

[@integral_chemistry]

I'm honestly not sure.. according to the arm and hammer website, their washing soda is the decahydrate, but you are right that the decahydrate readily effloresces to the monohydrate, but that only happens when it's exposed to air. So maybe it's the decahydrate when sealed but the monohydrate when left out? Not sure.. for this specific project it didn't seem to matter much but for other applications it definitely would so I would like to figure this one out.

[@jacobyoung7018]

@integralchemistry1849 I have had a box of arm and hammer washing soda sitting on a shelf for a few months, and I decided to evaporate off the water to get the anhydrous form and not a lot of water came off.

[@akirasantos5187]

How do you make a tetrahydrate cuso4 from pentahydrate

[@thepigdefenders2849]

just adjust the calculations according to the new water/cuso4 ratio

[@s9k328]

it is a mistake, he meant pentahydrate, see his comment here

[@WhileTrueCode]

music oddly reminds me of Neverwinter Nights... like im in town, buying Barkskin and Healing potions

[@ronritekinamatigai]

I don't think that fructose is a reducing sugar.
High fructose corn syrup is a mixture of glucose and fructose, and that's glucose that caused the reaction.

[@integral_chemistry]

I'll have to double-check but I'm pretty sure fructose is tollen's test positive for reduction. I'll test some pure fructose tomorrow and let you know

[@jimsvideos7201]

Neat.

[@dpasek1]

This might be a useful way to make pure Cu(I) oxide.

[@integral_chemistry]

That's something I was thinking actually^^ most other things I've tried turn out pretty impure. The decomposition of iron oxalate is also a really pure source of iron (III) Oxide on that note

[@VahidAlizadh-c1c]

Hello, are you active on Instagram?

[@rickrolls4928]

I’ve made Benedict’s reagent before

[@kanutaro3426]

That's my name!

[@nenben8759]

Forbidden gatorade

[@planellas6]

imagine being a doctor back in the day before modern diabetes screening procedures, the only way to tell if someone was a diabetic was to taste their urine. Wild, but look how far we have come now, now only kinky people do that sort of thing 😐

[@pphead6141]

Apoptosis would be amazing to have read you to sleep. His voice is so comforting. Formula for a perfect sleep would be cuddle his legs while he reads to you every night.