Back when toys were dangerous
I must be really old, because I once owned a chemistry set. Turns out, with evolving safety measures, this stopped being a toy of choice for curious boys around the time that we were putting people on the moon. Coincidence?
For those who never received such a Pandora’s Box, it contained a collection of test tubes, jars filled with odd rocks, and a guide to all that made science interesting in the home. Why, you could graduate from a home volcano, into crystal growing and getting into invisible inks. How did this all work?
Some of the chemicals were also found in the kitchen cupboard; vinegar (CH3COOH) and baking soda (NaHCo3) come to mind. We were ignorant to the chemical properties, but you could make a stinky, fizzy mess in one of those test tubes. Blow a cork across the room.
My recollections are vague, given the passage of time, but it seems that mixing a small spoonful of potassium permanganate (KmnO4) with water (H2O) gave one the necessary liquid to study invisible ink, as did a similar solution of copper sulfate (CuSO4) and water (H2O). Applied to paper, allowed to dry and then heated gently with a flame (alcohol lamp) proved to the fledgling chemist that not everything was visible to the naked eye. This wasn’t science as much as magic!
Today, decades later, I received some odour absorbing packets to put in my refrigerator, and the label made a point to show extreme caution, because the active chemical was potassium permanganate! Hey, I remember that name! Deadly poison? That wasn’t discussed, back in my younger days. We just knew better than to eat the stuff in the chemistry kit.
