Preparation of Silver Tetraiodomercurate(II) for a demonstration.

Silver Tetraiodomercurate(II) is a quite special compound, since it’s thermochromic. It changes color from yellow to orange/red when heated:

Silver Tetraiodomercurate (Ag2HgI4) is yellow at room temperature, but when it’s heated above 50 °C, it turns orange. Since the color change is reversible, when it is cooled back to room temperature, the color changes back to its original color.

The compound was prepared from mercury(II)-iodide (that red powder on the first picture) and some potassium iodide with a little silver nitrate. The silver nitrate was added to the solution of potassium tetraiodomercurate (K2HgI4,   what was previously prepared from mercury-iodide and potassium iodide). The addition of the silver salt caused the immediate precipitation of the yellow colored silver tetraiodomercurate (as seen on the gif).

What happened? This:

HgI2 + 2 KI + 2 AgNO3 –> Ag2HgI4 + 2 KNO3

anonymous asked:

Talk nerdy to me please because I love it immensely

The mitochondria… *takes off glasses….. is….*puts hair back*… the powerhouse of the cell. ;)


These are granules of wheat starch, stained with iodine, photographed through a common light microscope. 

Iodine is very much used to test for starch. In a solution of starch, if we put in iodine we see that it turns a dark blue almost black color sometimes. It is not clearly known how this happens, but they think that the iodine I3 and I5 ions fit inside the coils of amylose (starch chains), the charge transfers between the iodine and the starch, and “the energy level spacing in the resulting complex correspond to the absorption spectrum in the visible light region”. The more amylose in the solution the darker it gets. 


Because yesterday the whole amount of my compound decomposed to give a black tar, I have to prepare it again. One easy method for the production of iodinated compounds from bromine or chlorine substituted alkanes is the Finkelstein reaction.

What is the Finkelstein reaction? Finkelstein Reaction is a HalEx (Halogen Exchange) reaction what lets to change a bromine or chlorine to an iodine atom on an organic molecule. The trick is, that sodium iodide is well soluble in acetone (first pics), while the sodium chloride and sodium bromide is nearly insoluble. What happens is simple: R-X + NaI = R-I + NaX. The reaction is based on an equilibrium what only goes one direction, since the NaX gets removed from the reaction since it precipitates (third pics).  On the second pics the pressure tube was heated during the reaction what causes the product to decompose a bit and this is the reason of the yellow color. Luckily there is  alot stabilizer in the reaction mixture so at the end (third pics) only the precipitated sodium chloride is seen in the tube. 


So i have now chosen my 15 faves :)

They are:                              

Congratulations to all of you guys, love all of your blogs!!! 

So sorry to all of the people who weren’t chosen, but thank you so much for reblogging and i love you all xx

Chem & Bio Pick Up Lines
  • If I were an enzyme, I'd be DNA helicase so I could unzip your genes.
  • You're so hot, you denature my proteins.
  • Can I be the phasor to your electron and take you to an excited state?
  • Are you made of Copper and Tellurium? Because you are Cu-Te
  • Do you have 11 protons? 'Cause you're Sodium fine!
  • Do you like Science? Because I've got my ion you!
  • You must be gibberelin, because I'm experiencing some stem elongation.
  • You make my anoxic sediments want to increase their redox potential.
  • Are you made of Nickel, Cerium, Arsenic and Sulfur? Because you've got a NiCe AsS!
  • Hey baby, will a little more alcohol catalyze this reaction?
  • Didn't you know that chemists do it periodically on the table?
  • I bet you're like calcium bicarbonate - if I get you wet, the reaction will be explosive!
  • Are you made of Fluorine, Iodine, and Neon? 'Cause you are F-I-Ne
  • Me and you would undergo a more energetic reaction then Potassium and water.
  • Are you a compound of Beryllium and Barium? Because you're a total BaBe.
  • Im more attracted to you then F is attracted to an electron.
  • I will fondle your vesicles while you caress my golgi body.
  • I want to work on your leucine zipper with my zinc fingers.
  • If you were oxygen, I would be an alkali metal so i could get in you and explode!
  • We fit together like the sticky ends of recombinant DNA.
  • You are the photon to my photosystem:you excite my electron until I reach my reaction centre.
  • You're hotter than a bunsen burner set to full power.
  • If I were a neurotransmitter, I would be dopamine so I could activate your reward pathway.
  • Hey, wanna put your alpha helix in my beta barrel?
  • Hey baby, why don't you get your ligase working on my okazaki fragment and lengthen my strand.
  • Hey, are you an alpha carbon, because you look susceptible to backside attack!
  • Do you want to extract some protein from my column?
  • According to the second law of thermodynamics, you're supposed to share your hotness with me.
  • Everyone knows its not the size of the vector that matters, but the way the force is delivered.
  • How about me and you go back to my place and form a covalent bond?
  • If I was an endoplasmic reticulum, how would you want me:smooth or rough?
  • We can make a mess as I've hired some lysosomes to clean up after.
  • My hypothalamus must be secreting serotonin because baby, I want you!
  • I wish I was an Ion so I could form an exothermic bond with you.
  • You’re so cute you make my zygomaticus muscles contract.
  • I wish I were Adenine because then I could get paired with U.
  • You’re like telophase, I admire your cleavage.
  • Hey baby, want to form a synapse with me and exchange neurotransmitters?
  • Hey baby, want to form a zygote?
  • It’s a good thing you've got evaporative cooling, cause I’m going to make you sweat
  • If I were a Shwann cell, I'd squeeze areound your axon and give you a fast action potential.
  • Want to be my substrate/enzyme?
  • If my right leg is the cell wall and my left the membrane, do you want to be the cytoplasm?
  • If you were a concentration gradient I'd go down on you.
  • If you were C6, and I were H12, all we would need is the air we breathe to be sweeter than sugar.
  • Whenever I am near you, I undergo anaerobic respiration because you take my breath away
  • I want to stick to u like glue-cose.
  • You must be the one for me, since my selectively permeable membrane let you through.
  • Can I be your enzyme? because my active site is dying for a chemical reaction.
  • You give me more jolt than a mitochondria!
  • Right now we’re just two RNA, but maybe we could transcribe together and become DNA.
  • I have a smooth endoplasmic reticulum but know that I like it rough, if you know what I mean.
  • I also prefer my ribosomes bound tight. Spin me round with your basal body and make sure it's turgid.
  • Do you like aerobic respiration as much as I do?

hey hannah i absolutely love your blog and it would make me so happy if i was chosen to be one of your favourites! either way though i’ll still adore you so have a lovely day/night!

cw weight gain

Narratives in fat and body acceptance about people who lose weight inexplicably are very common and take up more space than narratives about people who are in the same sphere and inexplicably put on weight. Are we still so afraid to talk about it? Even in an explicitly weight neutral/ fat positive space?

I say this because I have put on weight. I know why. It’s because I had iodine therapy for graves disease last year and now I have an underactive thyroid. It seems like I can’t talk about this anywhere, most certainly not in places beyond fat activism and, curiously, the narrative is very quiet within.

I feel quietly ashamed, like my body has betrayed me, and I am a fat activist. It’s hard not to feel the pressure that you must be in ~super love~ with your body all the time, and that’s why I think “body love” is a bit of an unsustainable thing (but it is a nice idea!) We live in a culture of weight hysteria. We live in a culture that doesn’t know what to do with people with disabilities and health conditions. The intersection of weight and disability is blurry, misunderstood, and demonised; and many people within “body positivity” fail to comprehensively understand the nuances of living in a body that is fat and disabled (not to mention fat and not white/ poor/ trans or a combination of those!)

Ignoring my feelings is counter-productive and only serves to internalise  shame when I need to draw attention to this shit many of us feel. Lots of people in body positivity circles are still trotting out the “good fatty” trope when it does harm. Some of us are bad fatties who are putting on weight and can’t control our disobedient bodies. And I want to be able to take up space physically and intellectually and have my body respected like it should be. When I am ashamed, I am quiet, and I am more inclined not to advocate for myself; I believe this only leads to negative medical (mental and physical) outcomes.

I’m a really fat person
with disabilities
and a fat activist
and I have put on weight
and fucking respect me.

Entry Wounds

Words: 1, 226
Notes: Another shorter piece for the weekend while I’m fixing and adjusting other things.  Thank you all for reading, and any comments, critiques, or suggestions are appreciated.

The needle is delicate and silent, fine as a strand of spider-silk there in his hand. He holds it in the same way he now holds her forearm, which is with the very tips of his gloved fingers, thumbs rested over the plunger and the pulse in her left wrist, respectively.

“All right,” Bruce says. “Which do you prefer – ‘one, two, three, and then go,’ or ‘one, two, and go on three’?”

A suture kit sits open on the table beside them. It is one of the only things left in the cruciform bunker they’ve spent the last few hours clearing, save for a hanging lamp and the two chairs on which they now sit. Gauze sponges, speckled with blood and iodine, have been piled into a stainless steel pan. The laceration itself is thin and red where the knife has sliced through her suit.

And Natasha could likely tell him it doesn’t matter, that she has at one point or another broken almost every bone in that arm he’s currently holding as though it is the stem of a heavy-headed flower.

(Her medical records can testify to all of it: contusions and hematomas, oblique and comminuted and transverse fractures, ballistic trauma and penetrating trauma and the honest, visceral brutality of blunt force trauma for good measure.

“Note scarring of plantar fascia, general peripheral neuropathy,” the typed report also reads, no doubt available in electronic form somewhere on the Internet by now. “Indicates prior encounters with bastinado and parilla interrogation methods.”)

But Natasha cannot tell him any of that, so instead she answers, “Do it on three, then. Three’s a good number.”

“For wishes, maybe.” The needle rests poised against her arm. “Ready?”

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