题干

9.关于下列说法正确的是(      )

A:蒸馏烧瓶可以用酒精灯直接加热

B:用容量瓶配制溶液时,如果试样是固体,把称好的试样用纸条小心倒入容量瓶中,缓慢加入蒸馏水到接近标线1cm~2cm处,用滴管滴加蒸馏水到标线

C:苯和水的混合物最好用蒸馏的方法进行分离

D:分液时,应将分液漏斗内上层的液体从上口倒出,下层的液体从下口流出

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D

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Canada Day

                                                                  

                                                                                                                              

      Since 1982, July 1st has been officially known as Canada Day. Canadians of all ages take part in this festival across the country.
  Canada Day is the year's biggest national party. In many towns and cities, the government organizes a lot of events, often outdoors. These include parades(游行), concerts, festivals, firework displays and ceremonies for new Canadian citizens(公民). The celebrations often have a patriotic mood. Canada's national flag, a symbol for Canada Day, can be seen everywhere and a lot of people paint their faces red and white, which are Canada's national colors. The celebrations in Ottawa, Canada's capital city, are especially grand and exciting.
  In the province of Quebec, many home rentals(租赁)start on July 1st and last for exactly one year, and many people in Quebec spend Canada Day moving from one house to another. So in Quebec, Canada Day is also known as Moving Day.
  Many organizations, businesses and stores are closed this day. Only some bookstores, ho spitals and gas stations may be open. Post offices are closed, too. As Canada Day falls in the Canadian summer holiday period, all schools are closed as well. In some areas, special services are provided for large events. The concerts, parades and festivals may cause some traffic jams.