1.简答题- (共1题)
2.单选题- (共11题)
A.节日燃放烟花爆竹产生烟尘 |
B.焚烧生活垃圾而产生的有害气体 |
C.建筑施工导致尘土飞扬 |
D.生物腐烂放出有毒气体 |
3.选择题- (共3题)
I love to tell the story about how I met my best friend---- Tiger. We met at the school fair. Each year, all the fourth-grade classes hold a school fair. Everyone in the fourth-grade works at the fair. Some sell ice cream, drinks and snacks. Others take care of the little children who ride the rides.
I got the second job and I've never regretted it, because that's where I met Tiger.
My job was to help little children get on the back of a little horse. I kept telling the children to wait their turn and holding ice cream for them while they rode about. One thing was clear to me. I was growing older and should be more responsible.
Suddenly, a boy came to the horse. He took the little horse's reins! The horse stopped, and the girl on its back started to fall. I was trying to reach the girl when I saw Tiger go by my legs. It held the horse's reins and pulled the horse away from my legs. I caught the girl just before we both hit the ground. The girl sat on top of me. She was laughing at the ice cream on my face. The horse's reins were in Tiger's mouth!
Thanks to Tiger's fast action, I saved the little girl. We were both heroes. And Tiger, the fastest dog I've even known became my new best friend.
I love to tell the story about how I met my best friend---- Tiger. We met at the school fair. Each year, all the fourth-grade classes hold a school fair. Everyone in the fourth-grade works at the fair. Some sell ice cream, drinks and snacks. Others take care of the little children who ride the rides.
I got the second job and I've never regretted it, because that's where I met Tiger.
My job was to help little children get on the back of a little horse. I kept telling the children to wait their turn and holding ice cream for them while they rode about. One thing was clear to me. I was growing older and should be more responsible.
Suddenly, a boy came to the horse. He took the little horse's reins! The horse stopped, and the girl on its back started to fall. I was trying to reach the girl when I saw Tiger go by my legs. It held the horse's reins and pulled the horse away from my legs. I caught the girl just before we both hit the ground. The girl sat on top of me. She was laughing at the ice cream on my face. The horse's reins were in Tiger's mouth!
Thanks to Tiger's fast action, I saved the little girl. We were both heroes. And Tiger, the fastest dog I've even known became my new best friend.
4.填空题- (共7题)
(1)降雨是自然界中水循环的一个环节,云南部分地区今年以来遭遇罕见特大旱灾.为缓解旱情,部分地区用飞机、火箭向云中播撒干冰、碘化银等进行人工降水.
①干冰用于人工降雨过程发生的是________变化(填“物理”或“化学”).
②碘化银(AgI),不溶于水,见光易分解生成一种金属和一种双原子分子.该金属在人工降雨中,充当冰核形成剂.碘化银分解的化学方程式是______.
③如图是A、B、C三个地区雨水的pH柱状图,其中________(填字母)地区的雨水是酸雨.
(2)电解水时,加入少量NaOH可以增强水的导电性,NaOH在电解前后不发生变化.现将0.1gNaOH溶解在99.9g水里,接通直流电源后,与电源负极相连的一端放出的气体是________,当溶液中NaOH的质量分数变为0.2%时,有________g水被分解.

我们的家乡是座美丽的滨海小城,这里三面环海,海洋蕴含着丰富的资源,以下是人们从海洋中获取某些物质的方法:
①膜法淡化海水获得淡水; ②蒸馏法从海水中提取淡水;③采用蒸发结晶的方法晒得粗盐;④开采出原油并进行分馏获得汽油、煤油等产品;⑤向粗盐的溶液中加入试剂制得精盐;⑥向海水中添加石灰乳,再向得到的沉淀中加稀盐酸,然后电解获得的氯化镁制得镁;⑦用贝壳(主要成分碳酸钙)制生石灰。
(1)请从物质变化的角度对上述方法进行分类:一类是________(填写序号),另一类是________(填写序号),你的分类依据是________。
(2)和①膜法淡化海水原理相同的一个实验操作是________,原理都是依据________不同将混合物中的各成分分离。
(3)在②蒸馏法淡化海水时水的三态变化过程首先是由________态变为________态的蒸发过程,然后是由________态变为________态的冷凝过程,这与自然界中________循环的原理类似。请描述蒸馏法淡化海水的微观过程________。
(4)在③海水晒盐的过程中,钠离子、氯离子、水分子三种微粒的运动状态是:首先在海水中这三种微粒处于________的运动状态(选填“自由”或“在固定位置振动”,下同),在晒盐过程中,________(填微粒名称)不断运动到空气中去,另两种粒子结合后处于________的运动状态以晶体的形式析出,跟该结晶微观过程正好相反的一个物理变化是________。
(5)在⑤粗盐精制的操作中为除去过量的碳酸钠、氢氧化钠,需要添加适量的稀盐酸,请写出稀盐酸和氢氧化钠的反应中,有效作用的粒子有________。
(6)贝壳制得的生石灰可用来做干燥剂,日常生活中常见的干燥剂除了生石灰干燥剂外,还有一种硅胶干燥剂,硅胶吸附性能高、化学性质稳定,其内部为毛孔网状结构,能够吸收水分,并将水分保留住。根据提供的信息分析他们的干燥原理是否相同?________,理由是________。
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【1】题量占比
简答题:(1道)
单选题:(11道)
选择题:(3道)
填空题:(7道)
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【2】:难度分析
1星难题:0
2星难题:0
3星难题:0
4星难题:0
5星难题:0
6星难题:5
7星难题:0
8星难题:8
9星难题:6