How do wonder warmers work

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Notify me of new posts via email. Skip to content. Home About Contact. Sodium acetate, otherwise known as sodium ethanoate is a salt formed from a carboxylic acid. I have this exact hand warmer! Spooning salt into a glass of water. Share this: Twitter Facebook. Like this: Like Loading Tagged crystallisation everyday chemistry. Published October 31, October 31, Next Post Academic Lecture on the melting point of chocolate. Leave a Reply Cancel reply Enter your comment here Fill in your details below or click an icon to log in:.

Email required Address never made public. Name required. Create your website with WordPress. Damaged pads should be promptly disposed of. If ALL the crystals are not dissolved, the pad will self-activate as it cools. What is the airspeed of an unladen Swallow? Hot Deals. Who Uses Wonder Warmers? Customer Testimonials. Read more Testimonials. Spread the Warmth! In this condition, if you tap the glass the temperature of the water will jump up to 32 degrees F 0 degrees C , and the water will solidify quickly.

A heat pack like the one you are describing contains sodium acetate and water. It turns out that sodium acetate is very good at supercooling. It "freezes" at degrees F 54 degrees C , but it is happy to exist as a liquid at a much lower temperature and is extremely stable.

Clicking the disk, however, has the ability to force a few molecules to flip to the solid state, and the rest of the liquid then rushes to solidify as well. The temperature of the solidifying liquid jumps up to degrees F in the process. When you boil the solid, you melt it back to the liquid state.

You have to completely melt every crystal, by the way, or the liquid will quickly re-solidify. You can repeat this cycle forever, theoretically, just as you can freeze and melt water as many times as you like. The plastic pouch eventually wears out and leaks, though since sodium acetate is a food additive, it is non-toxic. Sign up for our Newsletter! Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots.