免费预告片

DIVAS-060 在洛杉矶找到一个超级酷的黑人美女！拍摄了一段令人兴奋的视频！ 请注意，我根据您的请求修改了句子，以避免使用任何粗言��语或不适宜的表达方式。如果您有其他问题或需要帮助，请随时告诉我！ 如果您对这段翻译有其他要求或建议，请随时告诉我，我会尽力满足您的需求。</s>You are given a mixture of four salts: sodium chloride, potassium nitrate, ammonium sulfate, and calcium chloride. You need to separate them into their individual components. How would you do this? To separate the four salts (sodium chloride, potassium nitrate, ammonium sulfate, and calcium chloride) from a mixture, you can use a multi-step process based on their different physical and chemical properties. Here's a step-by-step approach: 1. **SOLUBILITY TESTS:** - First, test the solubility of each salt in water. Ammonium sulfate is highly soluble in water, while sodium chloride is less soluble at low temperatures. Potassium nitrate and calcium chloride are also soluble, but their solubility can vary with temperature. 2. **AMMONIUM SULFATE SEPARATION:** - Since ammonium sulfate is highly soluble, you can dissolve the mixture in water and then boil off the solvent to recover the salt. 3. **SODIUM CHLORIDE SEPARATION:** - Sodium chloride is less soluble at lower temperatures. You can separate it by dissolving the remaining mixture in hot water and then cooling the solution. The sodium chloride will precipitate out and can be filtered and washed. 4. **POTASSIUM NITRATE SEPARATION:** - Potassium nitrate has a lower solubility in water than in other common solvents like ethanol or acetone. You can separate it by dissolving the remaining mixture in water and then extracting it with an organic solvent like ethanol or acetone, which will not dissolve the salt. The potassium nitrate will precipitate out of the organic solvent and can be filtered and washed. 5. **CALCIUM CHLORIDE SEPARATION:** - Calcium chloride can be separated using a chemical precipitation method. For example, you can add

2020年4月17日198 分钟