What does one stick, two low, three rely on mean?

One sticker, two low and three rely refers to the matters to be paid attention to in the process of "filtering" operation

One sticker: refers to the filter paper should be close to the funnel wall, generally when the filter paper is pasted on the funnel wall, wet with water and squeeze out the bubbles, because if there are air bubbles will affect the filtration speed

Two low: first, the edge of the filter paper should be slightly lower than the edge of the funnel;

Second, throughout the filtration process, it is necessary to always pay attention to the liquid level of the filtrate to be lower than the edge of the filter paper. Otherwise, the filtered liquid will flow down from the gap between the filter paper and the funnel and flow directly to the receiver at the bottom of the funnel, so that the unfiltered liquid is mixed with the filtrate, and the filtrate is turbid, and the purpose of filtration is not achieved.

Three reliance: first, when the liquid to be filtered is poured into the funnel, the beaker spout of the beaker containing the liquid to be filtered should lean against the inclined glass rod (glass rod drainage);

The second is that the lower end of the glass rod should be leaning on the side of the three-layer filter paper (one side of the three-layer filter paper is thicker than the one layer of filter paper, and the three-layer filter paper is not easy to be broken);

The third means that the neck of the funnel should be close to the inner wall of the receiver receiving the filtrate.

One sticker. The filter paper should be close to the inner wall of the funnel.

Two low. The edge of the filter paper should be slightly lower than the edge of the funnel;

The liquid level of the filtrate should be lower than the edge of the filter paper.

Three by the eye. Beaker.

The mouth rests against an inclined glass rod;

The lower end of the glass rod should be leaning against the side of the three-layer filter paper;

The neck of the funnel should be pressed against the inner wall of the receiver receiving the filtrate.

Analysis: One sticker: When filtering, in order to ensure that the filtration speed is fast and to avoid the liquid flowing down the gap between the funnel and the filter paper, the filter paper should be close to the inner wall of the funnel, and there should be no bubbles left in the middle

Two low: if the edge of the filter paper is higher than the edge of the funnel, the liquid in the filter is very likely to overflow; If the liquid level in the funnel is higher than the edge of the filter paper, the liquid will also run down the gap between the funnel and the filter paper, which will cause filtration failure

Three leaning: the mouth of the beaker for pouring the liquid should be close to the glass rod, in order to make the liquid flow down the glass rod slowly and avoid the splashing of the liquid; If the lower end of the glass rod is close to a layer of filter paper, if the glass rod punctures the wet filter paper, the liquid will flow down the gap between the funnel and the filter paper, resulting in filtration failure, and leaning on the third layer of filter paper can avoid this consequence; The tip of the nozzle at the lower end of the funnel should be close to the inner wall of the beaker that accepts the filtrate, so that the filtrate can flow down the inner wall of the beaker and avoid the filtrate from splashing out of the beaker

The first filter paper is close to the inner wall of the funnel, and the second is that the edge of the low filter paper is slightly lower than the edge of the funnel, and the liquid level in the funnel is slightly higher than the edge of the filter paper. The bottom of the funnel is close to the filtrate, and the glass rod is lightly on the side of the three-layer filter paper. The beaker rests lightly against the glass rod.

One sticker: Wet the filter paper with water so that the filter paper fits snugly against the funnel wall.

One sticker, two low and three rely on the specific content: one sticker: the filter touch paper should be pasted on the inner wall of the funnel.

The beaker mouth rests against the tilted glass rod; The lower end of the glass rod should rest on one side of the three layers of filter paper; The neck of the funnel should be close to the inner wall of the receiver used to receive the filtrate.

1. One sticker: When filtering, in order to ensure the fast filtration speed and avoid the liquid flowing down the gap between the funnel and the filter paper, the filter paper should be close to the inner wall of the funnel, and there should be no bubbles in the middle.

2. Two low: the edge of the filter paper is slightly lower than the edge of the funnel, and the liquid level of the filtrate is lower than the edge of the filter paper. If the edge of the filter paper is higher than the edge of the funnel, the liquid inside the filter is likely to overflow; If the liquid level in the funnel is higher than the edge of the filter paper, the liquid will also flow down the gap between the funnel and the filter paper, resulting in stupid vertical filtration failure.

3. Three leanings: the mouth of the beaker for pouring liquid should be close to the glass rod, so that the liquid can flow down the glass rod slowly to avoid liquid splashing; If the lower end of the glass rod is close to a layer of filter paper, if the glass rod punctures the wet filter paper, the liquid will run down the gap between the funnel and the filter paper, causing the filtration to fail, which can be avoided by leaning on the three-layer filter paper. The tip of the lower end of the funnel should be close to the inner wall of the beaker containing the filtrate, so that the filtrate can flow down the inner wall of the beaker and prevent the filtrate from splashing out of the beaker.

Filtration considerations for chemical experiments

1. The mixture in the beaker should be stirred with a glass rod before filtration, and then filtered.

2. If the solution is still turbid after filtration, it should be filtered again until the solution becomes transparent.

3. Washing method of precipitation in the filter: add distilled water to the filter with a flask or dropper to make the water surface cover without sediment, and repeat 2 3 times after the solution is all filtered out.

4. The function of the glass rod in the filtration process is to drain the water.

One sticker: the filter paper should be close to the inner wall of the funnel. Two low.

The edge of the filter paper should be slightly lower than the edge of the funnel; The liquid level of the filtrate should be lower than the edge of the filter paper. Three-leaning: the beaker spout should rest against the inclined glass rod; The lower end of the glass rod should be leaning against the side of the three-layer filter paper; The neck of the funnel should be pressed against the inner wall of the receiver receiving the filtrate.

Analysis: 1. One sticker: In order to ensure the fast filtration speed, it is instructed to avoid the liquid flowing down the gap between the funnel and the filter paper, and the filter paper should be close to the inner wall of the funnel, and there should be no bubbles left in the middle.

2. Two low: if the edge of the filter paper is higher than the edge of the funnel, the liquid in the filter is very likely to overflow; If the liquid level in the funnel is higher than the edge of the filter paper, the liquid will also run down the gap between the funnel and the filter paper, which will cause filtration failure

3. Three supports: the mouth of the beaker for pouring the liquid should be close to the glass rod, so that the liquid flows down the glass rod slowly and avoids the splashing of the liquid; If the lower end of the glass rod is close to a layer of filter paper, if the glass rod punctures the wet filter paper, the liquid will flow down the gap between the funnel and the filter paper, resulting in filtration failure, and leaning on the third layer of filter paper can avoid this consequence; The tip of the nozzle at the lower end of the funnel should be close to the inner wall of the beaker that accepts the filtrate, so that the filtrate can flow down the inner wall of the beaker and avoid the filtrate from splashing out of the beaker

One sticker: the filter paper should be close to the inner wall of the funnel. Two low.

The edge of the forest attack on the edge of the filter paper is slightly lower than the edge of the funnel; The filtrate level should be lower than the edge of the filter paper. Three leanings: the beaker spout should be leaning against the inclined glass rod; The lower end of the glass rod should be leaning against the side of the three-layer filter paper; The neck of the funnel should be close to the inner wall of the receiving filtrate receiver.

1. One sticker: When filtering, in order to ensure that the filtration speed is fast and to avoid the liquid flowing down the gap between the funnel and the filter paper, the filter paper should be close to the inner wall of the funnel, and there should be no bubbles left in the middle. Mega positive.

2. Two low: if the edge of the filter paper is higher than the edge of the funnel, the liquid in the filter is very likely to overflow; If the liquid level in the funnel is higher than the edge of the filter paper, the liquid will also flow down the gap between the funnel and the filter paper, which will cause the filtration to fail.

3. Three supports: the mouth of the beaker for pouring the liquid should be close to the glass rod, so that the liquid flows down the glass rod slowly and avoids the splashing of the liquid; If the lower end of the glass rod is close to a layer of filter paper, if the glass rod punctures the wet filter paper, the liquid will flow down the gap between the funnel and the filter paper, resulting in filtration failure, and leaning on the three-layer filter paper can avoid this consequence; The tip of the nozzle at the lower end of the funnel should be close to the inner wall of the beaker that accepts the filtrate, so that the filtrate can flow down the inner wall of the beaker and avoid the filtrate from splashing out of the beaker

One sticker. Even if the filter paper is wet, it adheres to the inner wall of the funnel and does not leave air bubbles. (Prevent air bubbles from slowing down filtration.) ）

Two low. 1. The edge of the filter paper is slightly lower than the edge of the funnel.

2. The liquid level is lower than the edge of the filter paper. (Prevent liquid filtration from being unclean.) Three by the eye. 1. When pouring, the beaker should be close to the glass rod.

2. The lower end of the glass rod is against the three-layer filter paper.

3. The nozzle on the side of the lower end of the funnel is close to the inner wall of the beaker.