下列变化是化学变化的是（ ）
A．
石油炼制
B．
用中性洗涤剂洗碗
C．
粉尘爆炸
D．
自来水工业使用活性炭
A、石油炼制只是利用各种成分的沸点不同将其分离，此过程中没有新物质生成，属于物理变化．
B、用中性洗涤剂洗碗只是利用了洗涤剂的乳化作用，此过程中没有新物质生成，属于物理变化．
C、粉尘爆炸过程中有新物质生成，属于化学变化．
D、自来水工业使用活性炭是利用了活性炭的吸附性，此过程中没有新物质生成，属于物理变化．
故选C．
| 阅读短文，完成表格。 | ||||||||
| Dear Ms White, The office is looking for a student consultant (顾问) for the coming term. Could you help me find a person for this position before February12, please? The consultant's job is to meet with students to discuss problems, opinions and suggestions on school policies, present weekly spoken and written reports to the Student Affair Office, and attend different school meetings as the student spokesperson (发言人). He should be a full-time student of our school and be skilled in report writing and oral communication. It will be better if the applicant has worked as a student consultant before. We will offer 2, 000 yuan a term for this position, and the time required for this job is 15 hours A week. The e-mail address is: SAO-hr@sina.com. Thanks! Mr. Green | ||||||||
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