20-Pack Unknown Composition Ferrous Ammonium Sulfate Samples, 100g Each, Varying Iron 0.1-13% Racks & Stands_Wintrobe Stands 1-5 kb range during PCR-product

1-5 kb range during PCR-product analysis and short-fragment electrophoresis

Economy-format graphite crystal model showing the layered hexagonal structure and the weak interlayer bonds responsible for graphite's slippery

Higher-output 65-watt soldering iron with a wooden bakelite handle

Claisen adapter in heavy-duty borosilicate glass features two parallel necks with 19/26 sockets for vacuum distillation and chemistry procedures

20-Pack Unknown Composition Ferrous Ammonium Sulfate Samples, 100g Each, Varying Iron 0.1-13% Racks & Stands_Wintrobe Stands 1-5 kb range during PCR-productTwenty sample pack of 100g ferrous ammonium sulfate unknowns at 0. 1 13% iron, providing investigation material for analytical determination practice in chemistry student coursework.