1.计算题- (共2题)
(1)对苯二胺的相对分子质量 ;
(2)增塑剂中碳、氢元素的质量比 ;
(3)增塑剂中氧元素的质量分数 .(小数点后保留一位数字)
| 反应前 | 反应后 | |
实验数据 | 烧杯和稀盐酸的质量 | 石灰石样品的质量 | 烧杯和其中混合物的质量 |
150 g | 12 g | 157.6 g |
(1)根据质量守恒定律可知,反应中生成二氧化碳的质量为_________g。
(2)求该石灰石中碳酸钙的质量分数_________
2.单选题- (共14题)
A. 氯仿由碳、氢和氯三种元素组成
B. 氯仿是一种氧化物
C. 氯仿转化为光气是化学变化
D. 一个光气分子由4个原子构成
A.氧气的密度比空气略大﹣﹣用于急救病人 |
B.稀有气体的性质稳定﹣﹣作保护气 |
C.石墨能导电﹣﹣可作电极 |
D.干冰升华吸热﹣﹣用于人工降雨 |
A.用旧报纸制铅笔杆 |
B.少开私家车,多坐公交车 |
C.开发回收利用二氧化碳的新技术 |
D.深秋时节焚烧落叶 |
3.选择题- (共3题)
根据短文内容,从短文后的选项中选出能填入空白处的最佳选项。
The benefits of keeping a journal(日志)
If you want to grow, one important thing you should do is keep a journal. It may seem simple, but it can make a big difference in your life. I have been keeping journals for years. Writing all the lessons I learn and all the ideas I get has become a habit for me. {#blank#}1{#/blank#} Here are some benefits you will get by keeping a journal.
♦ It prevents you from losing an idea. Have you ever gotten an idea and lost it later because you didn't write it down? {#blank#}2{#/blank#} But then I developed the habit of writing down every idea that came into my mind as soon as possible. If I am away from my computer, I usually write it down on a piece of paper that I bring wherever I go. I will then transfer the idea to the journal in my computer.
♦ It helps you review all the lessons you've learned. By reviewing your journal, you can quickly see the lessons you've learned and the ideas you've gotten. {#blank#}3{#/blank#} You can use the ideas to propel yourself forward.
♦ {#blank#}4{#/blank#} After keeping a journal for years, you can look back at it and see how far you've gone. Things that were big problems in the past might seem small today. The raw ideas you had in the past have been realized today.
♦ It helps you expand your ideas. When you try to come up with a sentence to express an idea, you are thinking actively about it. {#blank#}5{#/blank#} In the end, you will expand your ideas.
A.I often experienced that myself.
B.It trains you to express your thoughts.
C.It allows you to see your progress over time.
D.Just use whatever tool you feel comfortable with.
E.Thinking actively helps you connect your idea to another idea.
F.And to be honest, I can't imagine what my life would be like without it.
G.Then you can do whatever necessary to avoid repeating the same mistakes.
4.填空题- (共2题)
①两个镁离子 ;
②2个硫酸根离子 ;
③最轻的气体 ;
④地壳中含量最多的元素 ;
⑤相对分子质量最小的氧化物 ;
⑥光合作用可以产生的含碳物质 .
(2)写出下列反应的化学方程式,标明①的反应类型
①铁丝在氧气中燃烧 .反应类型 ;
②验证气体是否是二氧化碳的原理: .

(1)图Ⅰ实验中发生反应的表达式为 .
(2)图Ⅱ实验的操作步骤如下:
①点燃酒精灯.
②撤去酒精灯,待试管冷却后松开弹簧夹.
③将足量红磷平装入试管中,将20mL的注射器活塞置于10mL刻度处,并按图Ⅱ中所示的连接方式固定好,再将弹簧夹紧橡皮管.
④读取注射器活塞的数据.你认为正确的实验操作顺序是 (填序号).
(3)按图Ⅱ实验完成后,注射器活塞将从10mL刻度处慢慢前移到约为 mL刻度处才停止.
(4)对照图Ⅱ实验,你认为图I实验有何不足之处?(回答一点即可)
(5)采用图Ⅰ所示装置实验后,发现测定出的空气中氧气的体积分数低于

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【1】题量占比
计算题:(2道)
单选题:(14道)
选择题:(3道)
填空题:(2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:5
9星难题:8