问题
不定项选择题
为测定某盐酸溶液中氢元素的质量分数．世博同学向一定质量的石灰石中加入 105.4g稀盐酸，充分反应后，得到溶质质量分数为10%的111g溶液，则稀盐酸中氢元素的质量分数为[ ]
A.10.5%
B.0.2%
C.5.1%
D.15%
答案
答案：A
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为测定某盐酸溶液中氢元素的质量分数．世博同学向一定质量的石灰石中加入 105.4g稀盐酸，充分反应后，得到溶质质量分数为10%的111g溶液，则稀盐酸中氢元素的质量分数为[ ]
A.10.5%
B.0.2%
C.5.1%
D.15%
答案：A
阅读下面短文，根据短文内容完成表格中所缺信息，每空一词。 Some birthday customs are quite similar in many parts of the world---- birthday candles, birthday games，and birthday cakes. But some customs are more specific to certain countries. Here are some children talking about their customs. Linda---I am fourteen. I come from Aruba. In our country, Children take something special to school for their classmates and all teachers. Each teacher gives the birthday child a small gift like a pencil, an eraser or a postcard. The birthday child is also allowed to wear special clothes instead of the school uniform. Lucy---I am one year older than Linda. Denmark is my country. A flag is flown outside a window to show that someone who lives in that house is having a birthday. Presents are placed around the child’s bed while they are sleeping so they will see them at once when they wake up. Tom---I am as old as Linda. I am from Brazil. The birthday child receives a pull on the earlobe(耳垂) for each year in my country. The birthday person also gives the first slice of cake to his/her most special friend or relative, usually mom or dad.
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