Rice digestion
Preparations: Check whether the power supply of the instrument is connected; whether the exhaust pipe is connected to the fume hood; whether the experimenter has worn the protective equipment; whether there are foreign objects on the cavity and rotor; whether the digestion tube is cleaned and dried;
① Accurately weigh 0.3g of rice (the rice can be properly crushed to speed up the reaction) ② Send the weighed rice into the bottom of the digestion tube (be careful not to stick to the wall of the digestion tube) ③ Add 7ml premium pure concentrated nitric acid ④ Plug the digestion tube plug and screw on the digestion tube cap ⑤ Put the digestion tubes into the turntable ⑥ Put the rotor into the digestion instrument and check whether it is placed stably ⑦ Close the instrument door and set the digestion program
![microwave digester](https://cdn.shopify.com/s/files/1/0647/9183/8945/files/IMG_9934_480x480.jpg?v=1678081916)
1) Click Settings to enter the digestion program setting page
2) Click Item Selection, add a new item (eg 1), and click Enter to confirm.
![microwave digester](https://cdn.shopify.com/s/files/1/0647/9183/8945/files/QQ_20230306142250_1_480x480.jpg?v=1678084689)
3) Click on the form to enter the digestion temperature and time. After the input is complete, click Save to store the digestion program.
![microwave digester](https://cdn.shopify.com/s/files/1/0647/9183/8945/files/QQ_20230306142258_480x480.jpg?v=1678084870)
4) Click on the form to enter the digestion temperature and time. After the input is complete, click Save to store the digestion program.
5) Click Start to start digestion. (At this time, the voice prompts, and the experiment starts)
![microwave digester](https://cdn.shopify.com/s/files/1/0647/9183/8945/files/QQ_20230306142305_480x480.jpg?v=1678084818)
6) After the digestion is completed, the magnetron automatically stops heating. (At this time, the voice prompts, the experiment is completed)
7) Wait for about 20 minutes, when the temperature drops to about 40°C, take out the digestion tube. Slowly unscrew the cap of the digestion tube to release the pressure. At this time, there will be acid gas overflowing, and the pressure relief hole should face the direction of the fume hood. After the pressure relief is complete, unscrew the digestion tube cap.
8) Constant volume, transfer the constant volume solution to the volumetric flask.