题干

NA为阿伏加德罗常数的数值,下列说法正确的是

C:标准状况下,22.4 L CH3OH含有NA 个CH3OH分子

A:常温下,23g NO2含有NA个氧原子

B:1 L pH=1的盐酸溶液中,含有0.1NA个HCl分子

D:0.5 mol Fe2+与足量的H2O2溶液反应,转移NA个电子

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答案(点此获取答案解析)

A

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     【甲】那水呢,不但不结冰,倒反在绿萍上冒着点热气,水藻真绿,把终年贮蓄的绿色全拿出来了,天儿越明,水藻越绿,就凭这些绿的精神,水也不忍得冻上,况且那些长枝的垂柳还要在水里照个影儿呢!看吧,由澄清的河水慢慢往上看吧,空中,半空中,天上,自上而下全是那么清亮,那么蓝汪汪的,整个的是块空灵的蓝水晶。这块水晶里,包着红屋顶,黄草山,像地毯上的小团花的小灰色树影;这就是冬天的济南。

     【乙】再看水,以量说,以质说,以形式说,哪儿的水能比济南?有泉——到处是泉——有河,有湖,这是由形式分。不管是泉是河是湖,全是那么清,全是那么甜,哎呀,济南是“自然”的情人吧?大明湖夏日的莲花,城河的绿柳,自然是美好的了。可是看水,是要看秋水的。济南有秋山,又有秋水,这个秋才算个秋,因为秋神是在济南住家的。先不说别的,只说水中的绿藻吧,那份儿绿色,除了上帝心中的绿色,恐怕没有别的东西能比拟的。这种鲜绿全借着水的清澄显露出来,好像美人借着镜子鉴赏自己的美。是的,这些绿藻是自己享受那水的甜美呢,不是为谁看的。它们知道它们那是绿的心事,它们终年在那吻着水波,做着绿色的香梦。淘气的鸭子,用黄金的脚掌碰它们一两下。浣女的影儿吻它们的绿叶一两下。只有这个,是它们的香甜的烦恼。羡慕死诗人呀!

同类题4

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    Here's a selection of festivals for tourists to the United States in summer.

San Francisco Silent Film Festival

    Films at this odd cinematic event have a variety of musical accompaniments, including piano and violin. It includes some classic silent movies. If you want to see them all, you can buy a festival pass.

May 29 to June 1; www.silent film. org

Union Street Festival

    This popular street fair stretches out over six blocks of the city, in the fashionable shopping area of Union Street. This year, there's beer, wine tasting and more separate themes–––fashion, cuisine, tech, locals craft, and health and fitness.

    June 7 to 10: www.unionstreetfestival.com

North Beach Festival

    This is San Francisco's oldest street party, with live entertainment, delicious food and arts and crafts. Situated in the Little Italy district, known for its associations with the “Beat Generation”, festival goers are guaranteed plenty of good Italian food. There is also as the “blessing of the animals”, a San Francisco tradition which takes place at the National Shrine of Saint Francis of Assisi (610 Vallejo Street) at 2 pm on both days of the festival

June 14 to 16; www.sfhorthbeach. org

Stern Grove Festival

    This is the oldest free summer arts festival of its kind in the United States, It includes a wide variety of acts, from the local symphony orchestra to well-known artists such as Smokey Robinson.

Sundays from June 22 to Aug 24; www.sterngrove. org