下列关于空气的说法不正确的是（ ）
A．空气是宝贵的自然资源
B．硫在空气中燃烧产生明亮的蓝紫色火焰
C．空气的某些性质能反映出其组分气体的性质
D．空气中的二氧化碳能导致石灰水试剂瓶内壁附着白膜
答案：B
题目分析：A、空气中的多种气体成分都是与人类至关重要的，是人赖以生存的资源之一，故选项说法正确．
B、硫在空气中燃烧，产生微弱的淡蓝色火焰，故选项说法错误．
C、空气的某些性质能反映出其组分气体的性质，如是无色、无味的气体等，故选项说法正确．
D、二氧化碳能与石灰水中的氢氧化钙反应生成碳酸钙沉淀和水，能导致石灰水试剂瓶内壁附着白膜，故选项说法正确．
故选B．
点评：本题难度不大，了解空气的重要作用、物质在空气中燃烧的现象、二氧化碳的化学性质等即可正确解答本题．
Our three-year-old daughter Becky wanted a dog. But we were too busy to buy one. One day, Becky ran in, shouting, “Mom! Come to see my dog!” Her face was red with 36 . I followed her to the bush and found a 37 ! He was hurt. Seeing me, he stood up 38 ! I could see his teeth! God! My mouth felt dry. “Don’t be afraid. That’s Mom. She 39 you, too.” Becky said. Then he became friendly. It was 40 ! I 41 to find my husband and told him about the wolf. We should have 42 the wolf, but Becky loved him. Besides, he was gentle(温柔的) to Becky. So we called the vet finally. Becky named the wolf (狼) Ralph , 43 she carried food to him every day. Later, Ralph got well. They played together in the daytime. At night, Ralph would return to the mountains. Sometimes he 44 but came back several days later. On Becky’s first day of school, we could see Ralph’s 45 . After the school bus left, Ralph lay by the side of the road and 46 . When Becky returned, he got happy again. This 47 throughout Becky’s school years. Twelve 48 passed. One day we heard that a she-wolf was killed. The other wolf was hurt and ran away. We were 49 about Ralph. That night, Ralph returned with a wound (伤). Fifteen-year-old Becky held his head and 50 him. We hope he could come through. However, he 51 . Becky cried. I noticed something strange in the bush — two little yellow eyes! Ralph’s 52 ! Before he died, Ralph 53 his child to us! He knew he would be 54 here, as he had been. Ralph, Ralph... I was 55 . “Don’t be afraid, little ... Ralphie. That’s Mom. She loves you, too.”
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