8th Singapore National Crystal Growing Challenge

Thank you for participating in this challenge. The details of the competition are given below. For safety reasons, all experiments must be performed under the supervision of a school teacher/lecturer.

Junior Level

Potassium Dichromate, K2Cr2O7

This chemical is a common inorganic chemical reagent, most commonly used as an oxidising agent in various laboratory and industrial applications(Wikipedia). Potassium dichromate is doubtless one of the most beautiful lab-grown crystals; it is a crystalline ionic solid with a natural bright, red-orange colour. We are looking for more symmetrical crystals (rectangular prisms). This is also a factor in this competition. Caution: it is very toxic and carcinogenic, so great care is required in its use. A vapour mask and good quality gloves are a must.

Senior Level

Nickel Sulphate Hexahydrate, NiSO4·6H2O

This is blue-green salt commonly used in laboratory as nickel source, it belongs to tetragonal system. You need to take extra precautions to exclude the formation of NiSO4·6H2O (green, orthorhombic system). At room temperature the heptahydrate will usually come out of solutions. The first problem is to get suitable seed crystals of hexahydrate. This is best done by seeding with a grain or two from the supply bottle that contains the hexahydrate. If the seeds growing from these grains are chunky instead of long, they are crystals of the hexahydrate. Caution: crystals deteriorate on standing. Crystals can be stored indefinitely in sealed bottle and/or controlled humidity.

Open Level

Theme: Amino Acid Crystals with Specific Colour

For this category, you are asked to grown single crystals of glycine, an organic compound with formula HO2CCH2NH2. It is the smallest of the 20 amino acids commonly found in proteins. For added flair, sprinkle drops of food colouring should be added to get an orange crystal. The main objective of this category is to provide students with an opportunity to exercise their creativity, individuality and scientific knowledge.

In order to compete in this category, participating institutions should have submitted entries at the junior or senior categories.

The details about the evaluation rubrics and criteria for judgement of the best crystals (for the year 2006) may be found in our Website:

CHEMICAL SUPPLIERS
Supplier / Telephone Number / Fax Number
Merck (S) Pte Ltd / 6890-6638 / 6890-6636
Regent Chemicals Pte Ltc / 6777-5775 / 6779-3037
Sigma-Aldrich Pte Ltd / 6779-1200 / 6779-1822
Tee Hai Chem Pte Ltd / 6862-5655 / 6862-5855

Caution: Please get the MSDS (Material Safety Data Sheet) from the supplier along the chemicals.