Archive for July, 2007

Colloidal silver and other nano-demos

Tuesday, July 31st, 2007

Demos, demos, nano demos. Let's see. There is always the old kinetics demo of iron and oxygen at different aggregations and concentrations. A nail in a bunsen burner is not expected to burn. Four aught steel wool, carefully cleaned of oils with acetone, will burn quite nicely in ...

Buffers

Tuesday, July 31st, 2007

Weak acids and bases, and the conjugates of same. Not the most exciting of times in chemistry demonstrations. So what? A quarter liter each one tenth molar ammonia water, acetic acid, ammonium chloride, and sodium acetate. Water to mix, and a pH meter to test. ...

Equilibria

Friday, July 27th, 2007

Still getting the hang of a blog. My friend asked ow I learnd, I think not. Demo today was a pH meter on camera, with four solutions of metal nitrates. Potassium is pH neutral, zinc is acidic, as are iron(III) and aluminum(III). For pH eductainment we have columns ...

Paramagnetism and the physical difference between liquid nitrogen and liquid oxygen

Tuesday, July 17th, 2007

Some experiments are such a kick. I missed this one, set it up nicely. Liquid nitrogen is N2(l), so the five valence electrons for four sp3 orbitals, really the numerical basis for the Lewis octet, I guess. Three are shared, a triple bond. All electrons are paired. It is presumed to be ...

Windy afternoon after brunch party

Sunday, July 15th, 2007

Gorillaz in the mix, and waves of wind in the maples and walnuts. I can even look at my north-east conus radar loop. Something’s coming down the pike. I really like this animation of the last hour of continental us doppler weather radar. Why? It justifies a huge monitor. Scrolling around ...