题目

质量相等、质量分数相同的两份稀盐酸分别与碳酸钠和碳酸氢钠完全反应，消耗碳酸钠和碳氢钠的质量( )A.碳酸钠多 B.碳酸氢钠多 C.一样多 D.无法确定 答案：【答案】B【解析】质量相等、质量分数相同的两份稀盐酸中含有氯化氢的质量相等，分别与碳酸钠和碳酸氢钠完全反应。设稀盐酸中含有氯化氢的质量为mg，反应的碳酸氢钠和碳酸钠的质量分别为x、y； 则=，解得x=g=g，则=，解得y=g，由计算结果可知：g＞g，则消耗碳酸氢钠多，故选B。Read the passage and fill in the blanks with proper words（在短文的空格内填入适当的词，使其内容通顺，每空格限填一词，首字母已给）A healthy mindThe brain is the most fascinating part of our body. Even though there has been all medical research, n1. really understands everything about it. Like the rest of our body, our brain needs to be cared for. The ways that we keep our mind healthy can be quite s2.. Getting a good night’s sleep, eating a balanced diet and taking deep breaths are all important methods of looking after both your body and your brain.Many people think their brain will slow down with age and their memory will get worse as a result. The t3. is, just like your body, you can also improve your mind. I’ve found I can improve my memory by i4. what I need to remember. For example, if I’m going shopping and I need bread, milk and a birthday card for my brother, I form pictures of a loaf of bread, a carton of milk with a cow on the front and a birthday card with a football on it.The same kind of method can be used with important dates. If you have a picture in your mind of a particular event, it’s much e5. to remember than just a number on a calendar.Another way of improving your mind is to make sure you r6. visit new places and have new experiences. Traveling more often has much more long-term benefits than you would have ever expected. Personally I find learning English is a great way to keep the brain working, but communication with others in any language is important. Having a c7. is much better for your brain than staring at a computer screen or at other people talking on TV.