火药不仅应用于军事，也用于____。

锌及其化合物用途广泛．火法炼锌以闪锌矿（主要成分是ZnS）为主要原料，涉及的主要反应有：

2ZnS（s）+3O₂（g）═2ZnO（s）+2SO₂（g）△H₁=﹣930kJ•mol^﹣1

2C（s）+O₂（g）═2CO（g）△H₂=﹣221kJ•mol^﹣1

ZnO（s）+CO（g）═Zn（g）+CO₂（g）△H₃=198kJ•mol^﹣1

（1）反应ZnS（s）+C（s）+2O₂（g）═Zn（g）+CO₂（g）+SO₂（g）的△H₄=____ kJ•mol^﹣1．

反应中生成的CO₂与NH₃混合，在一定条件下反应合成尿素：

2NH₃（g）+CO₂（g）CO（NH₂）₂（s）+H₂O（g）△H

该反应在一定条件下能自发进行的原因是____ 　；若该反应在一恒温、恒容密闭容器内进行，判断反应达到平衡状态的标志是____ ．

a．CO₂与H₂O（g）浓度相等           b．容器中气体的压强不再改变

c．2v（NH₃）_正=v（H₂O）_逆              d．容器中混合气体的密度不再改变

（2）硫酸锌可广泛用作印染媒染剂和木材防腐剂．ZnSO₄受热分解过程中各物质物质的量随温度变化关系如图1所示．

①写出700℃～980℃时发生反应的化学方程式：　____ 　，物质B的化学式是　____ ．

②硫酸锌分解生成的SO₂经下图2中的两个循环可分别得到S和H₂SO₄．写出循环I中反应2的化学方程式：　____ 　；循环II中电解过程阳极反应式是____ ．

某同学将显微镜的使用环节与目的相匹配，得到下列四组结果，其中错误的一组是（　　）

         Mother Hen’s family is very poor. They don’t have lots of money to buy food. Mother Hen often takes her children out to look for food. On a sunny day, Mother Hen plays with her children on the grass. She finds a grain(谷粒) of wheat (麦子). So she asks her children to plant (种植) it in the garden. But her children don’t do it. Mother Hen has to do it herself.

      A few months later, they get a lot of wheat. She asks her children, “Who would like to take the wheat to the store and get some flour?” But her children don’t want to do it. So she takes the wheat to the store and brings the flour home.

   After getting home, she asks, “Who will make some bread with the flour?” They all say,

“I’m not free.”

   When she makes the bread, she says to her children, “Who wants to eat the bread?”

“I do,” they all say.

“No, you can’t. You don’t do anything before I make the bread. You must know ‘No pains,

no gains(不劳无获).’ She doesn’t give any bread to her children and she eats the bread herself.