如图的装置中，干燥烧瓶中盛有某种气体，烧杯和滴管内盛放某种溶液．挤压胶管的胶头，下列与实验事实不相符的是（ ）
A．NH3（H2O含石蕊）蓝色喷泉
B．HCl（H2O含石蕊）红色喷泉
C．C12（饱和食盐水）无色喷泉
D．CO2（NaOH溶液）无色喷泉
A、因氨气极易溶于水，则挤压胶管的胶头，使烧瓶中的气压减小，且小于外界大气压，则形成喷泉，又氨水溶液显碱性，石蕊遇碱变蓝，故形成蓝色喷泉，故A与事实相符；
B、因HCl极易溶于水，则挤压胶管的胶头，使烧瓶中的气压减小，且小于外界大气压，则形成喷泉，又盐酸溶液显酸性，石蕊遇碱变红，故形成红色喷泉，故B与事实相符；
C、因饱和食盐水抑制氯气的溶解，则挤压胶管的胶头，气压变化不明显，则不会形成喷泉，故C与事实不相符；
D、二氧化碳易与NaOH溶液反应，则挤压胶管的胶头，使烧瓶中的气压减小，且小于外界大气压，则形成喷泉，又反应后的溶液为无色，故形成无色喷泉，故D与事实相符；
故选C．
Blood donation(献血), also called blood banking, is a wonderful thing to do. It is an easy and direct way to contribute to social work and help the community. It helps to save lives and helps those who are in need of blood due to bad condition or the heavy loss of blood during operations or in accidents. You are able to give or donate blood every three or four month, and it is a great way to make a huge difference to someone’s life and you can always be proud of it after making valuable contributions to society. Blood donation is not a big problem, but you need to keep a few points in mind. Before donating blood, make sure that the ferrum (铁) level in your body is high enough and for that you should take a healthy diet. Do not go for blood donation on an empty stomach. You should follow the correct process so that everything goes well. After having a balanced diet you will feel strong and comfortable to donate blood. Afterwards, you will not feel faint or weak. For required hemoglobin (血红蛋白) in your body, drink lots of juice and other drinks. Fruit juice, such as apple juice is very good for increasing the blood level in your body. For a good blood flow（流动） in your body, drink at least 6-7 glasses of water every day. Completely avoid a day before and after giving blood, taking alcohol (酒). Do not smoke half an hour before giving blood. When you are going for blood donation, be relaxed, which helps keep the right blood pressure（血压）. During the blood donation activity, take a deep breath and try to calm yourself. Don’t join in some other activities. When you donate blood, you are making the effort to save someone’s life. Blood donation is a very simple and fast process, but you need to take care of yourself after donating blood. Proper care helps to reduce side effects. The following are a few tips that will help you out. Take a rest for 15 minutes after the donation. It helps you to feel relaxed. Eat something and drink juice before leaving the blood donation center. Make sure that you have meals after donating blood. Smoking should be avoided for one hour after the process. Avoid some activities right away, for example, driving. Finally, be proud of yourself because you have done a great thing in helping to save someone’s life. Blood donation is a very important activity.
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