Dangers of Heating Zinc for Science Project

A. Hi Brian. Best of luck with your project, and thanks for being careful!

But 120 °F isn't even as hot as some places get in the summer. I just read that outside temperatures of over 130 degrees have been recorded. Your attic probably reaches 120 in the summer. Are you sure you have that temperature right? If you were welding or putting a cutting torch on zinc, I'd worry. Or if you were eating off a zinc-plated sheet I'd worry a bit.

I think your chief concern should be that nobody touches the metals and gets burned, and I'd suggest a warning sign to that effect.

Good luck!

A. Kid,

I have personally been quite sick by breathing the gaseous oxide of the metal in question. I was welding galvanized pipe and failed to note the direction of the wind. I was sick for a day.

I doubt that 130 degrees would cause any problem with it. I think that your investigation is in the direction of "specific heat". You will find listings of how much heat energy is required to increase each type of material, by weight, an equal amount.

A. Hi, John. As long as this fire pit is outside, which I would certainly expect, I don't think there is much of a problem. While the heart of a hot fire is hot enough to melt the zinc, and maybe to vaporize it, I think you'd find it hard to build a fire that would vaporize the zinc except in a tiny spot, and then only on the inside wall, not the outside wall. Welding is something else, involving way higher temperatures, and inhaling the fumes because you're staying very close to watch your work.

Zinc is not a toxic material but a necessary micro nutrient (cold prevention tablets are actually zinc supplements), and a normal outdoor exposure to the small amount from a camp fires wouldn't worry me personally at all.

Regards,

 Thanks, I'll be building my fire pit and passing on the design and information.

A. Hello Gene.

Zinc is not a toxin, it is an essential nutrient. But a gross overdose can be a nasty problem.

Zinc doesn't become "toxic" at any temperature, but what does happen at the vaporization temperature of zinc (about 1600 ° F) is that the metal turns to a gas, such that it can be easy to inhale an overdose if you are a welder.

An oven in the kitchen is for cooking food, and that's all it should be used for! It's not a question of what facets of which hobbies and science experiments and household repairs you can safely use your kitchen oven for :-)

Apologies if that sounds harsh, but the point is that if things are used for purposes for which they weren't intended, it simply isn't possible to acquire the necessary history, data, and experience for anyone to say what is safe and what isn't. For example, what do you mean by "heating zinc to 450 °F" -- it's probably something very different from the next guy. 100% pure zinc might be no problem, but leaded zinc might; solid zinc sheet ⇦ this on eBay or Amazon [affil links] might not be a problem but putting galvanized metal with a hexavalent chrome conversion coating into a heated kitchen oven might be crazy.

Please try to post the exact details of your question rather than casting it in the abstract. Thanks.

Regards,

A. Hi Joshua. Using the term 'toxic gases' will make it hard for you to understand the nature of the problem. Zinc is not a 'toxic gas'; it is an essential micronutrient. The problem is that welders heat a lot of zinc to the vaporization point, creating a cloud of zinc oxide, and then inhale it into their lungs, getting a gross overdose. By way of parallel, instead of taking one baby aspirin, they are swallowing the whole bottle.

In a world of non-inspected imported foods from every hovel in the world, listeria, salmonella, rodent droppings, and fecal coliform poisoning are legitimate concerns, but I truly doubt that zinc poisoning from lining your barrel grill is. But get a hot fire going with no food on the grill the first time.

Regards,

A. Hi Catherine. I wish there wasn't quite this level of fear about this important micronutrient...

You need water, but if you are submerged in it you'll fill your lungs with it and drown.
You need zinc as well, but if you weld a bunch of it, vaporizing it in the white-hot electric-arc heat and filling the air with clouds of it, you'll fill your lungs with it and probably get "metal fume fever".
A galvanized clothes dryer drum should be of no concern at all.

Regards,

A. Hi Gary. You can use either plain black steel (black iron) or stainless steel. I suspect the plain steel will be very affordable and the stainless not so much. But other readers should not take this as a clue unless they know exactly what they are doing because carbon monoxide poisoning is always a concern. Good luck.

Regards,

A. Hi Jennifer. Sounds like no problem to me.

Regards,