1.简答题- (共3题)
(1)若甲可以用于灭火,将甲通入紫色石蕊试液中,观察到试液变红色,发生反应的化学
方程式为__________。
(2)若甲是一种红色固体氧化物,将甲放入过量的稀盐酸中,观察到固体消失, 。
反应后所得溶液的溶质为__________。
(3)若甲含有4种元素且能与稀盐酸反应产生气泡。向甲的溶液中加入过量氢氧化钠溶液,发生反应生成乙和水,但无明显现象;向反应后的溶液中逐滴滴加稀盐酸,一段时间后产生气泡。甲与氢氧化钠溶液的反应方程式为___________。
(4)若一定量的甲与乙在一定条件下发生反应,下列情况与图像的对应关系正确的是 __________ (填序号)。

| 甲 | 乙 | y轴含义 |
A | 生石灰 | 水 | 固体质量 |
B | 铜锌合金粉末 | 硫酸铜溶液 | 溶液质量 |
C | 工业炼铁的尾气 | 氢氧化钠溶液 | 气体质量 |
D | 密闭容器中的空气 | 红磷 | 反应过程中容器内压强 |
(1)地壳中含量最多的金属元素是 。
(2)金属铜做导线是利用其延展性和 性。
(3)铁是应用最广泛的金属。工业常用赤铁矿(主要成分Fe2O3)和一氧化碳在高温条件下炼铁,该反应的化学方程式为_ 。
(4)实验室中用如下实验来研究铁、铝、铜三种金属活动顺序及其在活动顺序表中相对氢的位置。

①乙实验的现象为_______________________________________________
②若将上述实验之一替换掉一种药品,即可达成实验目的。说明具体的改进方法:________________________________________________
③按如图实验结束后,将乙、丙实验后的剩余物倾倒至一个烧杯中,充分反应。然后将甲实验的剩余物倒入此烧杯,无气泡产生。以下说法正确的是________(填序号) 。
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2.科学探究题- (共1题)
体操运动员在完成单杠、吊环项目时常用“镁粉”搓手,以起到防滑效果。某种“镁粉”中可能含有Mg、MgO、Mg(OH)2、MgCO3中的一种或两种固体,实验小组对其成分展开了探究。
已知:MgO+2HCl = MgCl2+H2O
MgCO3+2HCl = MgCl2+H2O+CO2↑
(1)探究“镁粉”中是否含有Mg和MgCO3
①取少量样品,如图所示进行实验。观察到a试管中有气泡产生,b试管中产生的现象是____________。则证明“镁粉”中一定含有MgCO3。

②为证明“镁粉”中是否含有Mg,小明将燃着的木条放在图中b试管口上方,木条熄灭。但同学们指出,该实验不能达成实验目的,需要将图中的澄清石灰水替换成__________。小明按照修改后的实验方案重复上述实验,观察到b试管口无明显现象,证明“镁粉”中______________。
(2)探究“镁粉”中是否还含有MgO及Mg(OH)2
(实验过程)
Ⅰ。用MgO、Mg(OH)2和MgCO3三种固体分别做性质实验。分别取0.5 g三种固体粉末,每次取样方法如下图所示:

逐滴加入相同溶质质量分数的稀盐酸直至粉末恰好消失。在下表中记录消耗的同浓度稀盐酸的体积(以下体积均在同一条件下测定,且保留到小数点后1位)
| MgO | Mg(OH)2 | MgCO3 |
消耗稀盐酸的体积 /mL | 10.4 | 7.2 | 5.0 |
Mg(OH)2与盐酸发生中和反应的化学方程式为_____________。
Ⅱ。取“镁粉”样品0.5 g,加入上述稀盐酸至粉末恰好溶解。此时消耗稀盐酸的体积约为5.3 mL。
(实验分析及结论)
“镁粉”不只含有MgCO3。理由是____________________________________
(实验反思)
为确定“镁粉”的具体成分,同学们认为还需要补充如下实验:分别取0.5 g“镁粉”和0.5 g_________,加入足量稀盐酸,测定生成的气体体积分别为119 mL和140 mL。由此可知“镁粉”中含有MgCO3的质量分数为___________,“镁粉”中除MgCO3外的另一种物质为_____________。
3.单选题- (共20题)

浅色镜片 深色镜片 浅色镜片
A.溴化银应避光保存 |
B.变色镜片可反复变色 |
C.变色镜片颜色变深的过程发生了化合反应 |
D.变色镜片中的氧化铜在变色过程中质量不变 |
A.氧气能助燃,可用于医疗急救 |
B.氢氧化钙显碱性,可用于中和胃酸过多 |
C.氢氧化钠固体易吸水潮解,可用于干燥二氧化碳 |
D.二氧化碳固体(干冰)升华吸热,可用于人工降雨 |
| A | B | C | D |
图示 | ![]() | ![]() | ![]() | ![]() |
现象 | 有大量气泡产生,生成的气体使澄清石灰水变浑浊 | 冷却后,打开弹簧夹,水被吸入瓶内,瓶内水面上升约1/5 | a中的气体能燃烧,产生淡蓝色火焰,b中的气体能使带火星的木条复燃 | 滴有紫色石蕊的溶液呈蓝色,加入稀盐酸后蓝色变为红色 |
结论 | 该粉末中一定含有碳酸钠 | 氧气约占空气质量的1/5 | 水是由氧气和氢气组成的 | 反应后的溶液一定不呈碱性 |
A.A | B.B | C.C | D.D |
A.用灼烧法鉴别羊毛纤维和棉纤维 |
B.用适量稀硫酸清除铁制品表面的铁锈 |
C.用适量熟石灰除去氯化钠溶液中少量的碳酸钠 |
D.用足量稀盐酸检验久置的氢氧化钠固体是否变质 |

A.该样品已完全变质 |
B.液体丙呈红色或无色 |
C.该样品中一定含有碳酸钙 |
D.白色固体甲可能为Ca(OH)2和CaCO3的混合物 |
A.加入过量稀盐酸,称量反应后溶液的质量为m1 g |
B.加入过量浓盐酸,产生的气体用氢氧化钠固体吸收,固体质量增加m2 g |
C.加入过量的氯化钙溶液,过滤,将滤渣洗涤烘干,称量其质量为m3 g |
D.加入过量的氯化钙溶液,过滤,将滤液蒸干,称量固体质量为m4 g |
4.选择题- (共26题)
In February of 2005, Phil Belfiore was teaching one of Robert Frost's poems “Stopping by Woods on a Snowy Evening.” He liked it that he recorded it on his home answering machine, which would lead to one of the most unusual1of his life.
When Phil returned from his vacation, he listened to his voice 2 One gentleman caller 3for dialing the wrong number. But, he added, he'd really 4the poem. Phil laughed and thought nothing more of it— 5the phone rang a few days later.
Phil 6John's hollow voice immediately, who said sorry to7, but he was calling to hear the8again. The two men talked. It turned out that his brother's phone number was9from Phil's by one digit(数字), thus the wrong number. Before hanging up, Phil told John to 10anytime, whether to hear the poem or just to have a chat.
That was 11 years ago. They've spoken on the phone a few times a month ever since. It is John who is 11the starter of most calls. However, Phil will ring if a long while has passed. Not 12 John has been in poor health. His special voice is just the 13of some heart trouble. They seem to always 14when there's been a big sports event. The man like to discuss 15most. John will also 16Phil on his life. Slowly, their conversations have grown much more 17 When asked what drew them together, Phil18that they were old friends. They planned to meet twice, but circumstances went19them. Their friendship is based on the simple act of picking up the phone. “My best friend is someone I've not yet met 20 ” says John. It's as simple as that.
In February of 2005, Phil Belfiore was teaching one of Robert Frost's poems “Stopping by Woods on a Snowy Evening.” He liked it that he recorded it on his home answering machine, which would lead to one of the most unusual1of his life.
When Phil returned from his vacation, he listened to his voice 2 One gentleman caller 3for dialing the wrong number. But, he added, he'd really 4the poem. Phil laughed and thought nothing more of it— 5the phone rang a few days later.
Phil 6John's hollow voice immediately, who said sorry to7, but he was calling to hear the8again. The two men talked. It turned out that his brother's phone number was9from Phil's by one digit(数字), thus the wrong number. Before hanging up, Phil told John to 10anytime, whether to hear the poem or just to have a chat.
That was 11 years ago. They've spoken on the phone a few times a month ever since. It is John who is 11the starter of most calls. However, Phil will ring if a long while has passed. Not 12 John has been in poor health. His special voice is just the 13of some heart trouble. They seem to always 14when there's been a big sports event. The man like to discuss 15most. John will also 16Phil on his life. Slowly, their conversations have grown much more 17 When asked what drew them together, Phil18that they were old friends. They planned to meet twice, but circumstances went19them. Their friendship is based on the simple act of picking up the phone. “My best friend is someone I've not yet met 20 ” says John. It's as simple as that.
All the foodies(美食家) in Shanghai know where to explore next. The world famous food guide, the Michelin Guide, updated its Shanghai edition(版本) on Sept 20.
The Michelin Guide rates(评价) restaurants with one to three stars. The French tire(轮胎) company Michelin first made the guide more than a century ago. But why does a tire company make food guides?
Back in 1900, there were not many cars in France. So the company made free motorist guidebooks, with a list of hotels and restaurants to visit. They encouraged people to drive more and to buy more tires. It turned out that the guidebooks were popular. Later, it became restaurant guidebooks we know today.
The restaurant reviews are written by a group of mysterious people--the Michelin inspectors(巡视员). The company hires(雇佣) inspectors, who are all cuisine(烹饪) experts, to visit restaurants just like common customers. Neither the restaurants nor the public know who they are and how many of them there are in the world.
The guides have come to 28 countries and areas. It arrived in Shanghai, its first stop in the Chinese mainland, in September 2016. Many people doubted whether a food guide from Westerners could understand the Chinese cuisine. The company argued that most of the Shanghai guide's inspectors are Chinese and from different parts of the country.
This year, four new restaurants have been added into the second edition. They are of different styles, including a Ningbo cuisine restaurant and a vegetarian(素食的) restaurant. According to the Michelin, more Chinese cities will have their own Michelin guides in the future.
增加:在缺词处加一个漏字符号(∧),并在其下面写出该加的词。
删除:把多余的词用斜线(\)划掉。
修改:在错的词下划一横线,并在该词下面写出修改后的词。
注意:1).每处错误及其修改均仅限一词。
2).只允许修改10处,多者(从第11处起)不计分。
On December 10th last year, we paid a visit of a high-tech agricultural garden. It took us one and a half hour to get there. The natural environment there was very pleased, and we could breathe fresh air. The intelligent glass greenhouse, where many kinds of fruits and vegetables were growing there, was really amazing. Though it was very cold outside, the greenhouse controlling by a computer could provide a proper temperature. That was also very interesting to be surrounded with different plants. We could see so many colorful fruits and vegetables in the greenhouse where all of us have never seen before. Luckily, we allowed to taste some of the fruits and vegetables. We really had the good time and learned a lot from the visit.
Two of the saddest words in the English language are if only. I live my life with the goal of never having to say those words, because they convey regret, lost opportunities, mistakes, and disappointment.
My father is famous in our family for saying, “Take the extra minute to do it right.” I always try to live by the “extra minute” rule. When my children were young and likely to cause accidents, I always thought about what I could do to avoid an “if only” moment, whether it was something minor like moving a cup full of hot coffee away from the edge of a counter, or something that required a little more work such as taping padding (衬垫) onto the sharp corners of a glass coffee table.
I don't only avoid those “if only” moments when it comes to safety. It's equally important to avoid “if only” in our personal relationships. We all know people who lost a loved one and regretted that they had foregone an opportunity to say “I love you” or “I forgive you.” When my father announced he was going to the eye doctor across from my office on Good Friday, I told him that it was a holiday for my company and I wouldn't be here. But then I thought about the fact that he's 84 years old and I realized that I shouldn't give up an opportunity to see him. I called him and told him I had decided to go to work on my day off after all.
I know there will still be occasions when I have to say if only about something, but my life is definitely better because of my policy of doing everything possible to avoid that eventuality. And even though it takes an extra minute to do something right, or it occasionally takes an hour or two in my busy schedule to make a personal connection, I know that I'm doing the right thing. I'm buying myself peace of mind and that's the best kind of insurance for my emotional well-being.
内容包括:
1).自我简介 2).写信目的 3).我们应该感恩(thankful) 4).推荐的理由 5).预祝活动成功
注意:1). 词数100左右;
2).可适当增加细节。
可以适当增加细节,以使行文连贯,字数100左右。
Dear Tom,
I'm so happy to write to tell you something about my new English teacher, Miss Lin.
Look forward to your early reply.
Yours,
Li Hua
可以适当增加细节,以使行文连贯,字数100左右。
Dear Tom,
I'm so happy to write to tell you something about my new English teacher, Miss Lin.
Look forward to your early reply.
Yours,
Li Hua
可以适当增加细节,以使行文连贯,字数100左右。
Dear Tom,
I'm so happy to write to tell you something about my new English teacher, Miss Lin.
Look forward to your early reply.
Yours,
Li Hua
阅读《辣椒》,完成后面问题。
辣 椒
辣椒世界上有些国家吃辣椒很厉害,如墨西哥、印度、匈牙利、朝鲜……中国某些省,如四川、湖南等也以吃辣椒出名。有些人嗜辣椒已经到了"无辣不吃饭"的地步。美国宇航员威廉。勒努瓦在宇宙飞行时也带着辣椒。有一位指挥家,他走到哪里,辣椒就带到哪里,就连参加英国女王宴请时,也照例带着辣椒酱,他解释说:"没有辣椒的饭菜好比是病号饭。"
辣椒原产美洲,17世纪传入我国,故亦称"番椒",又名"秦椒"、"大椒"、"辣茄".辣椒有几千个品种,仅我国四川的干辣椒就有100多种。辣椒有辣与不辣之分,甜椒不辣。云南有一种辣椒,其辣无比,只要舌尖稍微碰一下,就会使人辣得难受,疼痛万分。美国制药专家斯克维尔于1912年制定了测量辣度的方法,后来人们就以他的名字作为辣度的单位。植物病理学家曾用这种方法,测出甜椒的辣度为零,最辣的辣椒有300000斯克维尔。
①辣椒能把人辣出眼泪、辣出鼻涕、辣出汗水,不爱吃辣椒的人不禁要问:"人们何苦要吃辣椒?"②这是因为吃辣椒有3个好处:一是它的营养丰富;二是能驱风散寒;三是能增进人的食欲。③每100克辣椒的维生素含量大于100毫克,在蔬菜中占首位。④此外,辣椒还含有维生素B1、B2、胡萝卡素以及其他营养物质。⑤谚语曰:"三个辣椒,顶件棉袄".⑥辣椒中的辣椒素对人体具有刺激作用。⑦辣椒素一旦和舌头及嘴里的神经末梢接触,神经就迅速把"烧灼"信息传给大脑,大脑便让身体处于戒备状态,使心跳和脉搏加快,皮肤血管扩张,从而使人感到"发热".⑧大脑还同时指挥胃液和唾液的分泌,使胃肠蠕动加快,这就有利于消化,增进食欲。
辣椒,很多人越吃越想吃。据心理学家分析,吃辣椒后,"烧灼"信息使大脑把身体作为"受伤"对待,从而促进身体释放一种自体止痛剂。这种自体止痛剂就像少量麻醉剂,能起到一种轻微的欣快作用,使人产生精神快感,专家称此为"辣椒微醉".这也许是人们对辣椒越吃越爱吃的主要原因。
We all know that exercise is good for your health. But some kinds of exercise may be better than others. Running for example, may help to protect us {#blank#}1{#/blank#}heart disease and other health problems. Running also may help you live {#blank#}2{#/blank#}(long).
Recently, researchers studied more than 55,000 adults. About one-fourth of the adults reported running{#blank#}3{#/blank#}(regular). The study found these runners were considerably less likely than non-runners{#blank#}4{#/blank#}(die)of any form of disease, including heart disease.
D. C. Lee and the other researchers found that speed,{#blank#}5{#/blank#} (distant)and how often one runs made little difference in{#blank#}6{#/blank#}(reduce)the risk of death. The runners in the study averaged between 10 and 16 kilometers per hour. Mr. Lee says slower runners, and those who only ran once{#blank#}7{#/blank#}twice a week, were helped nearly as much as those who ran faster and further.
The researchers note that their study{#blank#}8{#/blank#}(base) on the participants' answering questions over the years. The study lacked complete information on {#blank#}9{#/blank#}these men and women ate and other facts about their lifestyles.
Researchers say this missing information could have affected the results. Still they hope their findings will motivate healthy adults to start running, a bit, down the road to live{#blank#}10{#/blank#}longer life.
Phone Soap: Charge and Clean Your Phone
You may charge your phone every day, but do you clean your phone as much? Whatever your hands touch, your phones touch. It has been discovered that some phones have 18 times more bacteria and viruses than any surface in a public restroom. So it probably won't surprise you that a 2011 University of London study found that one in six of our phones have bacteria and viruses on them—specifically, the bacteria called E. coli.
The research on bacteria and viruses led to the invention of Phone Soap. It is not actually liquid like dishwasher soap. It is a phone charger that uses the electromagnetic radiation (辐射) used in hospitals to kill 99.9 percent of bacteria and viruses, cleaning your phone while it charges.
“There are really certain types of bacteria and viruses that we should not be in touch with, and they are really on our phones,” says Wes Barnes, the Phone Soap co-founder. It all started while his cousin and co-founder, Dan LaPorte, was in his cancer research lab at college. “He realized he got the idea of getting rid of bacteria and viruses on the phones,” said Barnes. “In the lab they used UV-C light for destroying them. He realized this would be the fastest, most powerful way to kill any bacteria and viruses living on electronic machines.”
Phone Soap looks like a little metal suitcase. Your phone rests in to charge and get cleaned at the same time. Instead of plugging your phone into the wall, you'd plug it into the Phone Soap charger box. The process only takes a few minutes but, Barnes says, “The idea is that you can leave it in there overnight if you want to keep charging. Reflective paint keeps the light completely around the phone so it cleans the phone fully.”
The co-founders spent 2013 finding the right companies and they started shipping the product in late November. By last week's International Consumer Electronics Show in Las Vegas, Phone Soap was all grown-up. Both co-founders have left their previous jobs and are selling Phone Soap nonstop. “We're shipping almost more than we can handle each day,” Barnes says. “It's been a great adventure.”
Good morning everyone! Today I want to talk about how to deal with our children's homework. As we know, homework is a great way for children to develop learning skills. So as parents, you should pay attention to it.
{#blank#}1{#/blank#}
Avoid having your child do homework with the television on or in places with different noises, such as people coming and going.
Make sure your child has all the materials he needs.
Ask your child if special materials will be needed for some subjects and get them in advance.{#blank#}2{#/blank#}
Help your child use time properly.
Tell them not to watch TV unless they finish their homework in time.{#blank#}3{#/blank#}Don't let your child leave homework until just before bedtime.
When your child asks for help, provide guidance, not answers.
Giving answers means your child will not learn the material.{#blank#}4{#/blank#}At the same time, you should keep in touch with teachers, which shows your child that the school and home are a team.
{#blank#}5{#/blank#}
If your child has been successful in homework and is working hard, celebrate that success with a special event to make him happy.
I am sure your child will be interested in doing homework if you take my advice.
Thank you!
A. Praise progress in homework.
B. Tell your child how important homework is.
C. Make sure your child has a quiet place to do homework.
D. For example, you should buy some paper, pencils, dictionaries and so on when you do some shopping.
E. Make a set time each day for doing homework
F. Be positive about homework.
G. Too much help is bad for your child's study.
Sharon, Aged 22
The most important thing to keep in mind when going into high school is to be yourself. Besides, I don't know what your middle school was like, but high school teachers will not care about things such as how much homework you already have in one night. It's best to just learn to deal with things and manage your time wisely so you can achieve everything you need to.
Frank, Aged 21
I think almost every kid feels both nervous and excited before their first day. You will probably love it. I know I did. You should join some sports or activities that will make your high school experience more enjoyable. Good luck!
Eddie, Aged 20
When I started high school I was really nervous too, especially since I had been homeschooled all through middle school and didn't really know anyone. I suppose the best advice would be to just relax. The first couple of days can be a little bit hard, but things will become easier before you know it.
David, Aged 19
I'm not going to lie. The first day is kind of frightening(令人恐惧的). But you'll get used to it. Don't be afraid of anyone; upperclassmen will pick on you more if you let them know you're afraid. Just take it easy. Making some friends and staying with them will greatly help you get used to high school quickly. After the first week it's really not bad at all. Don't worry.
Sharon, Aged 22
The most important thing to keep in mind when going into high school is to be yourself. Besides, I don't know what your middle school was like, but high school teachers will not care about things such as how much homework you already have in one night. It's best to just learn to deal with things and manage your time wisely so you can achieve everything you need to.
Frank, Aged 21
I think almost every kid feels both nervous and excited before their first day. You will probably love it. I know I did. You should join some sports or activities that will make your high school experience more enjoyable. Good luck!
Eddie, Aged 20
When I started high school I was really nervous too, especially since I had been homeschooled all through middle school and didn't really know anyone. I suppose the best advice would be to just relax. The first couple of days can be a little bit hard, but things will become easier before you know it.
David, Aged 19
I'm not going to lie. The first day is kind of frightening(令人恐惧的). But you'll get used to it. Don't be afraid of anyone; upperclassmen will pick on you more if you let them know you're afraid. Just take it easy. Making some friends and staying with them will greatly help you get used to high school quickly. After the first week it's really not bad at all. Don't worry.
Sharon, Aged 22
The most important thing to keep in mind when going into high school is to be yourself. Besides, I don't know what your middle school was like, but high school teachers will not care about things such as how much homework you already have in one night. It's best to just learn to deal with things and manage your time wisely so you can achieve everything you need to.
Frank, Aged 21
I think almost every kid feels both nervous and excited before their first day. You will probably love it. I know I did. You should join some sports or activities that will make your high school experience more enjoyable. Good luck!
Eddie, Aged 20
When I started high school I was really nervous too, especially since I had been homeschooled all through middle school and didn't really know anyone. I suppose the best advice would be to just relax. The first couple of days can be a little bit hard, but things will become easier before you know it.
David, Aged 19
I'm not going to lie. The first day is kind of frightening(令人恐惧的). But you'll get used to it. Don't be afraid of anyone; upperclassmen will pick on you more if you let them know you're afraid. Just take it easy. Making some friends and staying with them will greatly help you get used to high school quickly. After the first week it's really not bad at all. Don't worry.
Dear Mr. Smith,
I am seeking an opportunity to work with World Destiny as a Computer Systems Manage. My professional experience and my awareness of your high reputation and great achievements have led me to want to work for World Destiny.
Since 1998 I have focused on computer-system design and training. As Systems Administrator for Newport Museum for the past two years, I have directed accounting, capital campaign and publication production. We designed the system from scratch, developing all applications, policies, procedures, and training programs. I was well prepared for such a challenge by my previous positions as a Systems Support Specialist and MicroComputer Assistant for the Imperial Corporation of America.
Over the years, I have worked with Novell, using programs including dBase, Wordstarand Microsoft Word. This familiarity with a variety of hardware and software has helped me to get up to speed on nearly any computer with a minimum training period.
Additional experience in other fields also adds my value to World Destiny. As a Market Research Coordinator for Cushman & Wakefield of California, I not only researched and maintained(维护)a comprehensive database of Silicon Valley, but also produced statistical and written reports that support Cushman & Wakefield' reputation. Previously, I organized companywide annual sales meetings for Qualogy, Inc.
Mr. Smith, while this experience more than qualifies me to join any number of successful companies, it is my personal goals that lead to my interest in being part of the World Destiny team. I believe my computer, promotional, and organizational skills, fueled by my beliefs, make World Destiny and me right for each other. Can we arrange an interview at your earliest convenience? I will call within the next week to arrange a meeting.
Sincerely,
Beth Henning
5.填空题- (共2题)
(1)从海水中获取氯化钠的方法是_________。
(2)海水淡化可缓解水资源日益短缺的状况。下列有关海水淡化的方法可行的是 。
A.用过滤的方法使海水淡化 |
B.用降温的方法将海水变成淡水 |
C.利用太阳能将海水蒸发再冷凝收集淡水 |

① 将100 g40℃时的NaCl和KNO3的饱和溶液分别降温至20℃,所得溶液的质量关系是NaCl ______ KNO3(“>”、“="”" 或“<”)
② 20℃时向两个分别盛有45 g NaCl和KNO3的烧杯中加水,完全溶解形成饱和溶液时,盛有_____的烧杯中需要加入更多量的水。
③ 将800 g溶质的质量分数为20%的NaCl溶液稀释为16%的NaCl溶液,用于农业选种,需要加入水的质量为________ g。
(1)下列食物中富含糖类的是 (填序号)。



A.面包 B.鱼肉 C.黄瓜
(2)运动饮料中常含有钠、钾、钙等元素,饮用这种饮料能为人体提供水和 填(营养素名称)。
(3)当人体内缺少钙时,可能患有的疾病是 (填序号)。
A.骨质疏松 B.夜盲症 C.佝偻病 D.坏血病
(4)X是合成维生素A的原料。物质甲和乙在一定条件下反应可生成物质丙和X,甲、乙和丙的微观示意图见下表。
物质 | 甲 | 乙 | 丙 | ![]() |
微观示意图 | ![]() | ![]() | ![]() |
X属于 (填“单质”或“化合物”)。
该反应中甲、乙、丙的质量比为23: 17: 1,则X中各元素的质量比为 。
6.实验题- (共1题)
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【1】题量占比
简答题:(3道)
科学探究题:(1道)
单选题:(20道)
选择题:(26道)
填空题:(2道)
实验题:(1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:5
5星难题:0
6星难题:10
7星难题:0
8星难题:7
9星难题:5