题干

某课外研究小组,用含有较多杂质的铜粉,通过不同的化学的反应制取胆矾.其设计的实验过程为:

(1)铜中含有大量的有机物,可采用灼烧的方法除去有机物,灼烧时将瓷坩埚置于____ 上(用以下所给仪器的编号填入,下同),取用坩埚应使____ ,灼烧后的坩埚应放在____ 上,不能直接放在桌面上.

实验所用仪器:a.蒸发皿   b.石棉网   c.泥三角    d.表面皿    e.坩埚钳   f.试管夹

(2)杂铜经灼烧后得到的产物是氧化铜及少量铜的混合物,用以制取胆矾.灼烧后含有少量铜的可能原因是 ____ .

a.灼烧过程中部分氧化铜被还原        b.灼烧不充分铜未被完全氧化

c.氧化铜在加热过程中分解生成铜      d.该条件下铜无法被氧气氧化

(3)通过途径II实现用粗制氧化铜制取胆矾,必须进行的实验操作步骤:酸溶、加热通氧气、过滤、____ 、冷却结晶、____ 、自然干燥.

(4)由粗制氧化铜通过两种斜径制取胆矾,与途径I相比,途径II有明显的两个优点是:____ 、____ .

(5)在测定所得胆矾(CuSO4•xH2O)中结晶水x值的实验过程中,若测定结果x 值偏高,可能的原因是____ .

a.加热温度过高                  b.胆矾晶体的颗粒较大

c.加热后放在空气中冷却          d.胆矾晶体部分风化.

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答案(点此获取答案解析)

c,e,b,ab,蒸发,过滤,产生等量胆矾途径 II消耗硫酸少,途径 II不会产生污染大气的气体,a

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    Travelling around the world with children is difficult enough, while attempting it without using motorized transport is even more of challenge.Even so, Dario Schworer a 42-year-old climatologist and mountain guide, and his 33-year-old wife Sabine are on a journey to do just that.

    The Swiss couple want to travel across the world's oceans and climb the highest mountain on every continent to promote Earth-friendly ways of life.

    "We are collecting good examples of dealing with climate change and living in harmony with nature and we want to spread such ideas." Schworer said."We want to help people affected by global warming and to inspire children for the future."

    Recently after having spent three months teaching children in the Everest region, the couple want to show it is possible to travel through the world's climate zones using just human-power and forces of nature.

    In the 47 countries they have visited they have collected 22 tons of trash, taught people in Ecuador how the sun's rays can be used to clean water and inspired a person in Chile to build a house on water with recycled plastic bottles as a foundation.They have also collected trash in the mountains of Nepal with school children.

    So far they have communicated with 45,000 children from South America, Australia and Asia, giving presentations about the importance of recycling and using alternative energy like solar and wind power.

    When they began their adventure in 2003 they had no children of their own.But since then two has become five: daughter Sabine is now five years old, Andri was born in Chile and baby Neo was born in Australia.

    Initially the couple thought they would complete their travels in four years, but now, they believe it could take seven more.

    "Since our belief is the need to respect nature, we travel only when conditions are good," Schworer said.