题干

某同学模仿物理课上学到的“串联电路”,设计了如下气体制取与性质验证的组合实验.打开分液漏斗活塞后,A中出现大量气泡,B中白磷燃烧,C中液面下降.请看图回答问题:
(1)B中白磷能够燃烧的原因是____ .
(2)D中反应的化学方程式为____ .
(3)E中的实验现象是____.
(4)用F装置收集气体的依据是____ .
(5)人教版高中教材《化学1》显示,过氧化钠(Na2O2)和二氧化碳反应生成碳酸钠和氧气,化学方程式为2Na2O2+2CO2═2Na2CO3+O2.小翔同学和小何同学分别设计了图甲和图乙的实验装置,检查气密性良好后进行实验验证.预热后对试管进行加热(2NaHCO3=△Na2CO3+CO2↑+H2O).观察到图甲浓硫酸中有气泡产生,蚊香熄灭.浓硫酸的作用____ .观察图乙中的蚊香燃烧更剧烈,说明有氧气产生.由资料和实验可得出的结论是____ .
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同类题4

任务型阅读

    To meet the global climate crisis that is approaching, big lifestyle changes are required of those of us. The good news is that our way of life can remain meaningful and worthy as our consumption becomes sustainable(可持续发展的).

    ____ Eat less meat and move toward a plant-based diet. This is one of the most effective things we can do because the food we now produce and consume is destroying the very ecosystems that we depend upon for survival. Here are some of the grim facts.

    The U. S. uses about one-half of its land for agriculture.____For example, the U. S. uses over 90 million acres of good agricultural land to produce corn, which is mostly fed to livestock(家畜).

    With 7.6 billion people on earth, the demand for food is enormous and constantly on the rise. It's easy to feel we can't make a difference____We should not ignore the power of the choices we make.

    Even one person can make a big difference by eating less meat and moving toward a plant-based diet and make contributions to the health of the planet as well as your own. Recognize how the food we eat is connected to other living beings. It often helps us make much wiser buying choices.____This way, we will help people around the world enjoy more eco-friendly and nutritious foods.

    ____When you change your diet to be more sustainable, you become visible proof that changing our food habits is doable, healthy, and enjoyable.

A. Little things matter in your relationship with the earth.

B. By buying mindfully, we support local, affordable agriculture.

C. But we can change our diet to heal the earth as we heal ourselves.

D. Unfortunately, the majority is used to raise livestock or for crops consumed by them.

E. Your choices create positive impacts on the food system and inspire the people around you.

F. There's one step you can take right away to reduce harm to Mother Earth.

G. We can try to reduce waste by using leftovers and eating the fresh produce we buy.