Hardware Chemicals #1: Hydrochloric Acid

Hydrochloric acid is an extremely useful and versatile chemical that has many uses around the home.

Its usefulness comes from the fact that it is a very strong mineral acid that is nonetheless generally safe to have around. This is because its bark is worse than its bite. In its concentrated form you’ll see white fumes coming off it, and if you catch a whiff of it it’ll hit you in the nose like a sledgehammer. This property alone is a strong deterrent for children and pets.But these fumes are only an irritant – they are not toxic.

If you get it on your skin it’ll sting, but it won’t burn (like sulfuric acid). And if you got it in your eyes, they’d probably survive, although it’d sting like hell. But you should be wearing safety glasses and gloves when handling it anyway.

And it’s cheap. A 20L drum from the hardware store will only set you back about $45. And because it’s concentrated, it’ll last you a long time.

So what can you do with it?

For a start, it is an excellent weed and grass killer. Make it up at about 10% (500mL in a 5L garden sprayer), add a few handfuls of salt, make the whole lot up to the 5L mark and away you go. Spray it on weeds and grass that you want to kill and you’ll start to see results within 24hr. And it doesn’t matter if some gets on the soil – there are plenty of things in the soil that will neutralize it.

And if you find something that will survive this brew (unlikely) then just increase the concentration.

It’s also an excellent chemical for rejuvenating driveways. Cement is essentially an alkaline composite. As it’s exposed to the sun and air it develops a coating of cement dust, largely composed of limestone (calcium carbonate). A 10% solution of hydrochloric acid will strip off this layer and restore it to pristine condition. A clean with a high pressure water cleaner afterwards will remove any water marks and give it a uniform look.

Have you had tiles put down and the tilers have smeared grout over the tiles? No problem – a 5% solution of hydrochloric acid will get it off easily.

What are Acids?

I think my first experience of acids was an episode of batman, where the penguin demonstrated the potency of the acid that he was about to dunk Batman in by inserting his umbrella in it. When he pulled it out, the part that had been inserted had completely dissolved.

And this is the view of acids that most people have – potent, nasty chemicals that dissolve everything in their path.

Well, although there are acids that can dissolve all sorts of things, there is no acid that will do to the penguin’s umbrella what happened on the show.

Essentially we can place acids into two categories – mineral acids and organic acids. Mineral acids attack metals mostly, whereas organic acids attack organic material.

Also, acids may be categorised according to their strength, with the vast majority of acids being weak acids, and our bodies are full of them – amino acids, fatty acids and so on.

There actually aren’t many strong acids, and only one of them (hydrochloric acid) is available to the general public in a concentrated form. Other strong acids are sulfuric, nitric, perchloric, and hydrofluoric. That’s pretty much it, although there are several mixtures that are used to provide extra potency. Aqua Regia is a mix of 1 part nitric to 4 parts hydrochloric. Piranha solution is a mix of hydrogen peroxide and sulfuric acid, and chromic acid is a mix of sulfuric acid and potassium or sodium dichromate.

Tomorrow we’ll look at hydrochloric acid and see what it can be used for around the home.


Useful Gadgets: Lint Magic

The right selection of chemical product is critical to cleaning a surface well. But in recent times, a number of products have come onto the market that rely on their physical properties to do the job.

The best one of these that I have seen is Lint Magic. The principle is pretty straightforward. We have all seen sticky rollers for collecting pet hairs, dust and lint. The sticky roller gets full, and you just peel a layer away to expose the next layer of sticky paper and so on.

But the Lint Magic is even simpler. The roller is a soft silicon material that is sticky. After you roll it on a surface and collect dust or lint (it’s a great spot cleaner for floors) you just wash it under the tap, and all the lint just washes off. As soon as it dries, it’s right to go again – of course if you’re cleaning a carpet you don’t even need to wait for it to dry.

All in all, it’s a very clever product.

BAM vs BAM vs BAM #2

BAM make an oven cleaner:

It’s a pretty good oven cleaner, but there’s something it’s better at – a laundry prewash or spot cleaner for oily or fatty stains, whether it be cooking oil or engine oil.

The reason it works so well is that unlike the noncaustic Mr Muscle oven cleaner, it comes out as a fine spray. It can be worked into the stain and rinsed out, or simply sprayed on and used as a prewsh. But wait at least 10 min to allow it to react before washing it. Let the chemical do the work.