Bookmarks are best made by the following methods: first, put your favorite leaves in strong alkali water with chopsticks, heat them on the fire until the mesophyll falls off, and then clamp the leaves that have fallen off completely with chopsticks. Second, put the leaves on the table, flatten them with a glass plate and put them in a sunny place. Third, take out the flattened leaves, draw your favorite patterns on them with colored pens, cut them with scissors, and tie ribbons at the long petioles, so that our leaf bookmarks are ready.

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Method for making texture bookmark:

Mesophyll will rot when it meets corrosive liquid. It will rot faster when heated. Veins are tough and not easy to corrode. So some leaves with hard leaves and tough veins can be made into veins bookmarks.

Tool materials: beaker, tripod, asbestos net, alcohol lamp, match, balance, old toothbrush, tweezers, watercolor pigment, colored silk thread, sodium hydroxide, 3% hydrogen peroxide and osmanthus leaves.

Production process:

1. Pour about 90 ml of water into a beaker, add 10g of sodium hydroxide to the water, put the beaker on an asbestos net, heat it with an alcohol lamp, and boil the solution.

2. Immerse the leaves in the solution, continue to heat for about 15 minutes, and gently stir with tweezers to separate the mesophyll and corrode evenly.

3. When the leaves change color and the mesophyll is brittle, take out the leaves with tweezers and put them in a glass filled with clear water.

4. Take the leaves out of the clear water and put them on the glass. Gently brush the front and back of the leaves with an old toothbrush in running water to brush off the soft parts of the leaves, revealing white veins. Soak the leaves in 3% hydrogen peroxide for 24 hours to make them pure white, then take out the leaves, wash them with clear water and drain the water droplets.

5. Put the vein in an old book or newspaper and press it dry.

6. Take out the flattened vein piece, and when the vein is dry, apply watercolor paint on both sides of the vein with a brush, and flatten it after it is slightly dry.

7. Take out the vein slice coated with pigment and tie a colored silk thread on its petiole to get a delicate and beautiful veins bookmarks.

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sodium hydroxide

Also known as caustic soda, caustic soda and caustic soda, it is a common and important alkali, and its English name is soda hydroxide.

Chemical formula NaOH

The formula is 40.0 1. The density is 2. 130g/cm3, the melting point is 3 18.4℃ and the boiling point is 1390℃. Pure anhydrous sodium hydroxide is a white translucent crystalline solid. Sodium hydroxide is very soluble in water, the solubility increases with the increase of temperature, and a lot of heat can be released when dissolved. Its aqueous solution has astringency and satiny, and the solution is strongly alkaline, which has all the commonalities of alkali. There are two kinds of caustic soda sold in the market: pure solid alkali is white, blocky, flaky, rod-shaped, granular and fragile; Pure liquid alkali is a colorless and transparent liquid. Sodium hydroxide is also soluble in ethanol and glycerol; But insoluble in ether, acetone and liquid ammonia. Corrosive to fiber, skin, glass, ceramics, etc. When dissolved or diluted with concentrated solution, heat will be released; The neutralization reaction with inorganic acids can also generate a lot of heat and generate corresponding salts; Reacting with metallic aluminum and zinc, nonmetallic boron and silicon to release hydrogen; Disproportionation reaction with chlorine, bromine, iodine and other halogens. Can precipitate metal ions in aqueous solution into hydroxide; It can saponify oil and generate corresponding sodium salts and alcohols of organic acids, which is the principle of removing oil stains from fabrics.