Within the school program in physics the seventh-graders are offered to grow up independently from salt crystals.
It is required to you
- - two heat-resistant tanks
- - water - 100 ml
- - table salt - 1 pack
- - tablespoon
- - gauze or sieve
Instruction
1. Carrying out experience on cultivation from crystal salt in house conditions requires two containers not less than 250 ml. One of them will be metal that it was possible to boil in it water, other glass, for example, usual jar of 0.5 liters.
2. In metal capacity pour cold water, bring to boiling and remove from fire. Let's water cool down and again boil it. Then again cool and again bring to boiling. Now on one tablespoon fill usual table salt in the container with the boiling water. Add salt until it does not cease to be dissolved. The turned-out strong salt solution - - pour a brine, using a gauze or a sieve, in heat-resistant capacity. If you use a glass jar, pour hot liquid gradually, in the small portions, differently bank can burst and you draw to get burns. Leave salt which was not dissolved in metal capacity to next time. Cover capacity with a brine a piece of a gauze or any other fabric and leave on 1 - 2 day.
3. After this time carefully merge liquid in metal capacity from the residues of salt. Attentively examine a deposit at the bottom of banks. Choose several transparent crystals which still absolutely small size. Shift other salt in metal capacity. Warm up liquid before boiling, stir residues of salt and if necessary add fresh salt. Again filter liquid in bank, observing precautionary measures. When liquid a little cools down, mix it a spoon and lower the chosen crystals in liquid.
4. To bank cover with fabric again and leave for 1 - 2 day. Repeat manipulations with liquid heating until receive crystals of the satisfactory sizes.