Calcium carbonate is also used in the purification of iron from iron ore in a blast furnace. The carbonate is calcined in situ to give calcium oxide, which forms a slag with various impurities present, and separates from the purified iron.
One re-hydrated package fills about 15-20 dishes. Mix 1 level teaspoon of dehydrated agar with 100 ml (3/8 cup) of water and then bring to a boil to make 100 ml of agar solution. Prepare Petri Dishes: Fill petri dishes to just cover the bottom. Typical 90-100mm dishes require 10-15 ml agar. Rotate the dish to obtain even surface coverage. Cover the dish immediately and let stand until firm. Store upside down in the refrigerator until ready to use.
1 Now it s time to collect and grow your bacteria (or fungi) on the agar Petri dishes. 2  Note: the Petri dishes can be stored in the fridge for 1-2 days before use.3  Bacteria is not hard to collect because it is everywhere. Immediately put the lid back on the Petri dish and put it in the fridge for about 4 hours until the agar has set. 2  Do not touch the agar or you will contaminate it with bacteria on your fingers. 3  Now it s time to collect and grow your bacteria (or fungi) on the agar Petri dishes.