Zinc Sulphide 250g

While litmus paper may be used to determine whether an aqueous solution is an acid or a base, it not good for estimating the pH value of the liquid.

Aluminium Foil

Aluminum foil is suitable for many laboratory application, including sealing bottles, culture tubes,  , reducing evaporation or heat losses, covering corks, making weighing boats or dishes. May be used to cover vessels for autoclaving and incubating.

Potassium hydroxide, also known as _lye_ is an inorganic compound with the chemical formula KOH. Also commonly referred to as caustic potash, it is a potent base that is marketed in several forms including pellets, flakes, and powders. It is used in various chemical, industrial and manufacturing applications.