Views: 16 Author: Site Editor Publish Time: 2019-06-06 Origin: Site
Gel is often encountered in daily life, such as fish and so on when cold will freeze slowly, this phenomenon is more obvious in winter. Solid alcohol is the common gel in our lives. How is it made?
Experimental principle
The alcohol and water can be mixed in any ratio, and calcium acetate is dissolved in water only and is not soluble in alcohol. When the saturated calcium acetate solution is injected into the alcohol, the water in the saturated solution is dissolved in the alcohol to separate the calcium acetate from the alcohol solution to form a semi-solid gel substance.
This is the gel.
As the wine is filled, the alcohol burns up when the gum is ignited.
Experimental supplies: spoon, beaker, measuring tube, glass rod, evaporated dish, match, alcohol (mass fraction more than 95%), calcium acetate, distilled water
The experimental steps are as follows:
1. The saturated solution was prepared by adding 20m1 distilled water and adding proper amount of calcium acetate to the beaker.
2. Add 80m1 alcohol to the beaker, then slowly add 15m1 saturated calcium acetate solution, stir continuously with glass rod, the substance in the beaker appears turbid at the beginning, continue to thicken and stop flowing, and finally become gel.
3. Remove the gel, pinch it into a ball, and light it in an evaporating dish. The jelly caught fire at once and flared blue.
Note:
1. The solubility of calcium acetate in water does not decrease with the increase of temperature, so the saturated solution of calcium acetate should not be heated, but only with water at room temperature.
2. Alcohol is volatile in the gel, and a large amount of gel should be sealed when frozen. The dialectical thought of "practice first" is helpful to the formation of facts.
Expand knowledge:
Put the fruit (such as apple) into the sugar and boil it into a glass to cool it to make a gel.
Colloidal solutions made of adding a small amount of dry glue (such as gelatin) to the water can also be turned into gel. (10% of the gelatin solution can be solidified into gel in only 10 minutes)
