题干

下列卤族元素的有关实验,说法正确的是

A:往稀米粥中加入少量加碘食盐,能检验食盐中是否含碘

B:已知I3- I2+I-,向盛有KI3溶液的试管中加人适量CCl4,振荡静置后CCl4层显紫红色,说明KI3在CCl4中的溶解度比在水中的大

C:用溴水即可鉴别苯酚溶液、2,4-己二烯和苯

D:浓盐酸长期暴露在空气中因为见光分解而浓度降低

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C

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    Would it surprise you to learn that, like animals, trees communicate with each other and pass on their wealth to the next generation?

    UBC Professor Simard explains how trees are much more complex than most of us ever imagined.

    Although Charles Darwin thought that trees are competing for survival of the fittest, Simard shows just how wrong he was. In fact, the opposite is true: trees survive through their co-operation and support, passing around necessary nutrition “depending on who needs it”.

    Nitrogen (氮) and carbon are shared through miles of underground fungi (真菌) networks, making sure that all trees in the forest ecological system give and receive just the right amount to keep them all healthy. This hidden system works in a very similar way to the networks of neurons (神经元) in our brains, and when one tree is destroyed, it affects all.

    Simard talks about “mother trees”, usually the largest and oldest plants on which all other trees depend. She explains how dying trees pass on the wealth to the next generation, transporting important minerals to young trees so they may continue to grow. When humans cut down “mother trees” with no awareness of these highly complex “tree societies” or the networks on which they feed, we are reducing the chances of survival for the entire forest.

     “We didn't take any notice of it,” Simard says sadly. “Dying trees move nutrition into the young trees before dying, but we never give them chance.” If we could put across the message to the forestry industry, we could make a huge difference towards our environmental protection efforts for the future.