Acid test?

[ScottJ]

I don't want to go buy a whole bottle of muratic acid to test a couple ingots for zinc.

Would extra electrolyte from one of those fill it after buying lawnmower batteries do for the acid to check for zinc?

[Rocky Raab]

Back in my "basement bomber" days of mad chemistry, I used battery acid to create hydrogen gas from zinc chips. So, yup, if it bubbles under battery (sulfuric) acid, it's probably not lead.

Just pop the battery cap and suck up a few drops as needed with an eye dropper. Rinse the eye dropper well with a baking soda solution afterward, and (must I say this?) always wear eye and skin protection.

[ScottJ]

Thanks. I don't have to steal it from the batt.

I got more than I needed to fill the batt I bought back in the Spring. Being the sort who rarely throws stuff out the bottle of extra has been sitting tucked away on a corner of my workbench.

[markinalpine]

I think the reason Muriatic acid is so often recommended it that it is relatively available and not THAT expensive. I bought a quart bottle for about $0.79
Sulfuric Acid isn't always that easy to come by, especially if you live in a small town, as I do, or are out in the country.

Mark

[ScottJ]

Interesting, I've only found muriatic in gallons for around $3.00. I don't really need it often enough to justify having a gallon around.

[Bent Ramrod]

Sulfuric acid, diluted in water for battery use, will work fine. The reaction with lead will be very slow, just a bubble once in a while, and the lead sulfate byproduct will be an insoluble white solid. Zinc will emit a steady fizz of small hydrogen bubbles from all over the surface of the metal and in addition, zinc sulfate should dissolve readily in the battery acid.

As with all chemical tests, it's best to have a piece of known lead and known zinc so you can see what the reaction is like before testing unknown samples.

[XWrench3]

well, you learn something new every day (actually, i don't, as i don't get out much). so, i do not mean to hijck this thread, but could you use muratic acid to "eat" the zinc out of ingots if you find ingots with zinc in them? or would you have to grind it all up into powder (which i have no way of doing, and would not anyway....to dangerous). although, i might be able to talk my brother into letting me use his mill too "chip" it up.

[felix]

Too nasty of a job for the rewards. Health hazards galore. ... felix

[ScottJ]

Too nasty of a job for the rewards. Health hazards galore. ... felix

I agree. If mine had been zinc contaminated I would have just designated them for fishing sinkers or something like that.

[Shiloh]

I think the reason Muriatic acid is so often recommended it that it is relatively available and not THAT expensive. I bought a quart bottle for about $0.79
Sulfuric Acid isn't always that easy to come by, especially if you live in a small town, as I do, or are out in the country.

Mark

Plus it doubles as a very effective brass cleaner for heavily tarnished or dirty brass.

Dilute, soak for a few minutes, rinse well, dry, polish as usual.
Comes out looking new.

Shiloh