题干

化学与生活密切相关。下列说法正确的是(   )

A:燃煤中加入生石灰可以减少酸雨的形成及温室气体的排放

B:对医疗器械高温消毒时,病毒蛋白质受热变性

C:钢铁在海水中比在河水中更易被腐蚀,主要原因是海水含氧量高

D:NaHCO3能与碱反应,因此食品工业上可用作焙制糕点的膨松剂

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答案(点此获取答案解析)

B

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    More than anything else in the world, Lion liked being King of the jungle.  He walked around, showing off his power and pride.

    Each day Lion took a long lazy sleep under the shade of his favorite tree.  He always dreamed of weaker animals bowing(鞠躬) before him.

    One day Mouse ran through the jungle and tripped over Lion's huge paws.  Lion woke up with a start. “How dare you wake me up!” he shouted angrily. Lion grabbed(抓住) Mouse with one paw. “On the second thought, I'm in the mood for the snack, and you'll make a delicious meal.” he said.

    Mouse cried out, “King Lion, please spare(饶恕) me! If you let me live, I'll always remember your kindness.  And, some day, I might be able to help you.”

    “How could such a powerless little mouse ever help me?” That thought made Lion laugh so much that he decided to let Mouse go.  A week later, Lion was walking through the jungle on the way to his favorite tree when he stepped onto a hunter's net.  The net scooped him up. No matter how he twisted (扭动) and turned, he couldn't escape.

    When Mouse heard Lion's frightened shouts, he raced to help. Mouse quickly chewed(咬)through the ropes to make a hole in the net.  Soon, Lion moved out and was free. Lion looked down at the little mouse. “Thank you for saving my life,” said Lion, smiling his widest smile.  “I was mistaken.  You are not a powerless little mouse. You are a great friend!”