浙江省杭州市萧山区高桥初中教育集团2020-2021学年第二学期期中考试质量检测科学试题

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【真题首发】浙江省杭州市萧山城区2021-2022学年八年级下学期期中质量检测语文试题(含答案)

【真题首发】浙江省杭州市萧山城区2021-2022学年八年级下学期期中质量检测语文试题(含答案)

2021学年第二学期八年级期中学科质量检测语文试题卷(试卷总分值120分考试时间120分钟)一、积累(20分)为了让同学们更好地传承中华文化,当好亚运东道主,学校广播站拟播出一期以“舌尖上的杭州”为主题的节目,请你帮播音员小西和小湘完成以下任务。

【开场白:食之韵】1.根据拼音,填写汉字。

(3分)富(shfi)D浮(zdo)D(ping)口吊2.填入横线处的词语,恰当的一项为哪一项()(2分)A.行色匆匆B.惊慌失措C.束手无策3.划线句子有一处语病,请作修改。

(提出修改意见,2分)【探源头:食之器】2021学年第二学期八年级期中检测语文参考答案及解析一、积累(20分)1.庶躁凭(3分,每空1分)【解析】此题考查字形的掌握,根据平时对字词的积累,以及语段的内容,可知答案为“庶”“躁” “凭”。

汉字的音与形是密不可分的,大局部汉字字形不同,读音不同,意义不同,平时的学习中应注意区分多音字、形近字和形声字等,努力做到不误读,不误解,不误写。

2.B (2 分)【解析】此题考查词语(成语)的运用,“行色匆匆”的意思是“形容出行时的匆忙仓促" “惊慌失措”的意思是“害怕紧张,以至不知所措、失去常态”,“束手无策”的意思是“像捆住手似的,一点方法也没有,形容遇到问题时毫无解决的方法”,结合语境B项符合题意。

3.“检测”改为“猜想”或“揣测”(2分)【解析】此题考查学生对于语病的判断能力,根据语境,“检测”和“心态”搭配不当,“检测”为“检查测试”,可改为“猜想”或者“揣测”。

4.C (3 分)【解析】此题考查古代文化知识和信息获取分析能力,根据图表和知识积累可知A、B、D 项正确,C 项“令尊”应是“对对方父亲的敬称”。

5.①落英缤纷②往来翕忽③柳宗元④气蒸云梦泽⑤青青子衿⑥原是对人的深切思念,此寓美食让人念念不忘(意对即可,但需写出原意和寓意)⑦知己楼\比邻府等⑧天涯假设比邻(8分,每空1分,有错字不得分)【解析】此题考查学生对古诗文名句的识记理解能力,第6和第7空可仿照所给例如,联系诗句、店名以及诗句本身含义得出答案。

2020-2021学年浙江省杭州市萧山区八年级下学期期中考试科学试卷

2020-2021学年浙江省杭州市萧山区八年级下学期期中考试科学试卷
C.钓鱼杆导电了
D.小鸟只能落在零线上,落在火线上同样将被电死
6.下列用微观图示表示的物质变化,属于化学变化的是( )
A.①②B.①③C.②③D.①②③
7.在直流电动机中,当线圈转到什么位置时,换向器能自动改变线圈中的电流方向( )
A.线圈转到任意位置B.线圈平面与磁感线平行
C.线圈平面与磁感线垂直D.线圈平面与磁感线成45°角
A.莽草酸中氢元素的质量分数最大
B.莽草酸由碳、氢、氧三种元素组成
C.莽草酸中各元素的质量比为7:10:5
D.每个莽草酸分子里含有5个氢分子
3.如下图所示的四幅实验装置图中,肯定不能反映电动机工作原理的是()
A.
B.
C.
D.
4.触摸电冰箱门时手感到了“麻
A.火线断路
B.火线与电冰箱的金属外壳漏电
C.火线与零线相碰
D.电冰箱的金属外壳接了地
5.用电安全是天大的事,在随州曾发生过这样一幕惨剧,在某农户的鱼塘上空有高压线通过,一位钓鱼者抬杆取鱼时,钓鱼杆触及电线,钓鱼者当场被电死。下面说法不正确的是()
A.此高压线是裸导线(导线外没有绝缘皮)
B.钓鱼杆接触到了火线
8.下列四幅图中哪一幅图所示的做法没有违反安全用电的原则()
A.
B.
C.
D.
9.一台电动割草机应该在插头中装上10安的保险丝,可是小玲误装了3安的保险丝。这台割草机将()
A.正常运转B.烧断保险丝C.割起来快D.割起来慢
10.家用漏电保护器是在用电器发生漏电故障或人体触电时实施保护的设备,家庭电路漏电时,通过火线与零线的电流不相等,漏电保护器中有一特殊装置(在图中虚线框内,未画出)检测到这一差异后,便切断电源,起到保护作用,漏电保护器中还有试验电路,由一只开关S与电阻R组成,闭合开关S就能模拟漏电情形,试验电路的连接符合要求的是

浙江省杭州市萧山城区六校2020学年第二学期八年级期中语文参考答案

浙江省杭州市萧山城区六校2020学年第二学期八年级期中语文参考答案

2020学年第二学期八年级期中学科质量检测语文试题卷参考答案1.(1)翘(2)滞(3)犹(3分,每个1分)2.(1)B(2)B (2分,每个1分)3. D (3分)4. B (3分)5. B (3分)6. (1)窈窕淑女,君子好逑(2)悠悠我心子宁不嗣音(3)黄发垂髫,并怡然自乐(4)俶尔远逝,往来翕忽(5)海内存知己,天涯若比邻(6)气蒸云梦泽,波撼岳阳城(共6分,每句1分,多字漏字错字均不得分)7. 傅聪傅敏(每空1分,共2分,错字不得分)8.示例1:我认为傅雷称得上是完美父亲。

傅雷在生活上对傅聪的关心是无微不至的,虽远隔重洋但是对儿子的嘘寒问暖从未停歇。

如他凭着自己对欧洲的了解,推测那里的天气、人事及风俗习惯等,提醒儿子如何适应环境,对儿子交友、理财婚恋等,傅雷更是苦口婆心。

此外,傅雷能走进儿子的内心世界,父子俩平等地探讨音乐和艺术,傅雷鼓励傅聪汲取艺术精华,教育傅聪不忘祖国文化。

由此可见,傅雷不愧为完美父亲。

示例2:我认为不能说傅雷是个非常完美的父亲。

因为世界上不存在完美的人,傅雷在傅聪小的时候,管教方式显得过于严苛,对傅聪的身心造成了伤害,后来他悔恨不已,通过写家书的方式走进儿子的内心世界。

我想和天下所有的父亲一样,傅雷虽然不完美,但他努力做一个优秀且尽可能完美的父亲,这在他的《傅雷家书》中有着充分体现。

(有观点有分析,结合名著情节分析,合理即可得满分3分)9.(1)宽大的河道边 (2)草地上 (3)浴缸里 (4)马桶里(每空1分,共4分)10.一波三折使故事跌宕起伏,引人入胜,更能引起读者的阅读兴趣和好奇心。

一开始鱼被带到上游,以为水质会好一些,但是没想到呛得鱼咳嗽,只能拉到岸上,但是鱼没有水不能活,于是被带回家放到浴缸里,没想到人们每天使用的水也有问题,最后鱼跳到马桶里,扎入下水道不见了。

鱼四处奔逃, 让故事更有可读性,令人欲罢不能。

而鱼无论奔逃到哪里,都没有它的容身之处,突出了文章主旨。

2021年浙江省杭州市萧山区高桥初中教育集团中考英语二模试卷(附答案详解)

2021年浙江省杭州市萧山区高桥初中教育集团中考英语二模试卷(附答案详解)

2021年浙江省杭州市萧山区高桥初中教育集团中考英语二模试卷一、完形填空(本大题共15小题,共15.0分)(2021·浙江省杭州市·模拟题)As a kid,I used to spend my summers with my grandparents on their farm in Texas.I helped them (1)______ farming at times.Luckily,they(2)______ a caravan,a kind of car designed for people to live in while traveling.Every few summers,we'd travel together around the US and Canada.On one (3)______ .I was about 10 years old.I was playing around in the back of the car(4)______ my Grandfather was driving.My grandmother had the passenger seat.She smoked through the trip,and I hated the(5)______ ,which made me cough a lot.I read about smoking in an article.It says that every puff (吸)of a cigarette takes two minutes off your life.I(6)______ the number of cigarettes per day and the puffs per cigarette.When I came up with a reasonable number,I was (7)______ .Then I moved my head into the front of the car and proudly (8)______ ,"So far,you've taken nine years (9)______ your life!"Hearing this,my grandmother began to cry and it was not what (10)______ .I did not know what to do.My grandfather,who had been driving(11)______ stopped the car ,got out of it and (12)______ my door.He looked at me calmly,and said(13)______ ,"See,grandmother is crying!One day,you'll understand that it's harder to be(14)______ than clever."As I grow up,I realize that cleverness is a gift and kindness is a choice.Gifts are easy---they are given (15)______ .Choices can be hard,so it seems more difficult to be kind.1. A. with B. for C. in D. like2. A. produced B. owned C. required D. returned3. A. picnic B. trip C. flight D. ride4. A. as B. when C. while D. though5. A. dust B. taste C. noise D. smell6. A. guessed B. counted C. collected D. received7. A. afraid B. relaxed C. satisfied D. worried8. A. replied B. explained C. presented D. announced9. A. to B. on C. off D. from10. A. dreamed B. enjoyed C. supported D. expected11. A. in fear B. in silence C. with pride D. with sadness12. A. opened B. closed C. turned D. changed13. A. gently B. loudly C. powerfully D. confidently14. A. calm B. kind C. brave D. strong15. A. in all B. after all C. above all D. first at all二、阅读理解(本大题共15小题,共30.0分)(2021·浙江省杭州市·模拟题)ANight Noodle MarketsDreaming of some fantastic family entertainment?The Night Noodle Markets could be just what you and your family are looking for.Tasty food. Delicious smell at the Night Noodle Markets Enjoy the Asian-style street food.Great locations. Top outdoor dining at all the main squares of your city.Take a look at the menus on offer. Click on the icons below.When?Monday to Saturday 5 pm to 11 pm.Where?Click HERE to find a Night Noodle Market in your city. Supported by Drinko Soft Drinks Nifty Noodles Local councils16..What is ?______A. The name of the owner.B. The address of the website.C. A collection of food.D. The name of the markets.17.. When can people go to the markets?______A. At 3 p. m. on MondayB. At 11 a.m. on Tuesday.C. At 9 p. m. on Sunday.D. At 10 p. m on Thursday.18.. The main purpose of the advertisement is to ______ .A. encourage people to go and eat at the marketsB. tell people the features of delicious Asian foodC. ask people to choose the food pictures they likeD. introduce some supporting companies to people(2021·浙江省杭州市·模拟题)B"I want a mobile phone!" said Lisa."I'm sure you do," said her dad."No,Dad.You don't understand.I really,really,really want a mobile phone.""And I really,really,really want a boat.It's not going to happen."Lisa and her dad were stuck in traffic.It seemed that it's always the case.When he took her to school in the morning — traffic.When he picked her up in the afternoon — traffic.Go to the supermarket,a birthday party,and what felt like ten hours of traffic was what they got.Lisa was bored.When she was bored,she wanted things.Right now,she wanted a mobile phone.She wasn't sure if her dad understood that.She would have to tell him again."I WANT A MOBILE PHONE."NO.""What if I got stuck in a cave?""What?" asked her dad,trying not to laugh."What if I had a dog and the dog ran away,and I had to run after it.What if the dog ran into a cave,and I ran after the dog.In the cave there was a bear,and the bear trapped me,and …" "And then you were stuck in the cave.""Yes.It's a mother bear.She will eat me unless I have a mobile phone to call for help.""If it's a mother bear,you can use her phone.Everyone knows mums always carry phones." Dad was laughing as he said this.Lisa didn't think it was very funny.Now she was angry."If I had a mobile phone,I could play games on it!""If I had a boat,I could eat beef on it.That doesn't mean I'm getting one.""No,but I mean if I could play games,I wouldn't be so bored when we were in traffic.I wouldn't trouble you!""I don't mind being troubled.I like talking to you.""Then I won't say anything at all!"Dad smiled quietly to himself. "I'm going to call Mum to let her know we'll be late." He reachedinto his pocket. "Oh!My battery's dead.""You know…if I had a mobile phone,I could call Mum," said Lisa."Nice try."Lisa smiled.She wasn't getting a phone,but she knew she was right,and that was almost as good.19.What happened to Lisa and her dad?______A. They couldn't find their dog.B. They were stuck in traffic.C. Their car broke down.D. They lost their way.20.What does the underlined word "one" refer to?______A. a game.B. a piece of beef.C. a boat.D. a mobile phone.21.Which of the following is NOT the reason why Lisa was angry?______A. She failed in making Dad buy her a mobile phone.B. Dad didn't want to buy her a mobile phone.C. She would get home late today.D. Dad was making fun of her.22.How did Lisa feel at the end of the story?______A. Bored.B. Excited.C. Worried.D. Calm. (2021·浙江省杭州市·模拟题)CWorld Sea Turtle Day:Don't Let It Swim Away Celebrated on June 16th,World Sea Turtle Day is to show us one of the world's oldest and most fascinating sea animals,Unluckily,this is also a special day to remind everyone of the sea turtle's terrible situation.Sea turtles have been around for millions of years.Spending most of their lives at sea,most of them live to be 30 to 50 years old.But some can live to be as long as 150 years.They can hold their breath for up to five hours.This helps them dive into the deep sea and stay there longer.Sea turtles also like to get around,often swimming very long distances.One kind of sea turtles can move over 12,000 km from the beaches in Japan all the way to the feeding ground near Mexico.That's an unbelievable ability.Female sea turtles return to the beach to lay eggs.Some lay up to 250 eggs in a single nest,and each egg takes around 60 days to incubate and then it becomes a cute baby turtle.But it's a pity that only one in a thousand baby turtles can grow up.World Sea Turtle Day also has a more serious purpose.What is it?All seven kinds of seaturtles are in great danger.Plastic trash is a big part of the problem because the turtles often mistake bags and other plastic products for food.In fact,half of all sea turtles have eaten plastics in their lives.Rising temperatures on the earth are another danger that turtles face.Turtle eggs that lie on warm sand are more possible to result in female turtles,which affects the animals' diversity (多样性).Also,trash-covered beaches can make it hard for baby turtles to reach thesea.Finally,some people use turtle shells to make handicrafts,because of their beautiful patterns.Even if these handicrafts break the laws,they are still found in places around the world. So if you want to celebrate World Sea Turtle Day,take some time to spread the word about what we can do to protect these ancient animals.Reducing the amount of plastics we use and throw away is just the key.23.What's the most amazing thing about sea turtles?______A. They can live a long time.B. They can hold their breath for hours.C. Some of them can move very far.D. Some of them can lay a lot of eggs in a nest.24.What's the meaning of the underlined word "incubate" in Paragraph 3?______A. Be stored there to keep fit.B. Be kept warm till a life is born.C. Get bigger to prepare for life.D. Hide there to stay away from danger.25.Which of the following facts have caused sea turtles to be in great danger?______①long living at sea ②plastic trash "food" ③trash-covered beaches④the killing of humans ⑤more and more female turtles ⑥rising temperatures on theearthA. ①②③④⑤B. ①②③④⑥C. ①③④⑤⑥D. ②③④⑤⑥26.What does the passage mainly want to tell us?______A. Sea turtles are a kind of amazing sea animals.B. Sea turtles have been found to be in great danger.C. World Sea Turtle Day is a special day for sea turtles.D. We're supposed to understand and protect sea turtles.(2021·浙江省杭州市·模拟题)DA new study found that cleaning your teeth often every day was linked to a lower risk for heart problems such as heart failure (心衰竭)and atrial fibrillation(心房颤动).What the study found was that brushing your teeth three times a day or more was linked to a ten percent lower risk of atrial fibrillation.It was also linked to at twelve percent lower risk of heart failure.The researchers examined information on more than 161,000 people in Korea with no history of heart problems.They followed up ten and a half years later,and found that three percent had developed atrial fibrillation and almost five percent had developed heart failure.All the participants(参与者)in the study aged 40 to 79 had usual medical exams between 2003 and 2004.Information was collected on their height,weight,laboratory tests,sicknesses,and lifestyle.They also noted their mouth health in connection with cleaning.You may wonder how teeth health and heart health are connected.Earlier research suggests that not taking care to clean and brush teeth leads to bacteria in the blood.This can increase the risk for unusual heartbeat and heart failure.A study last year by the American Heart Association showed that brushing your teeth twice a day for at least two minutes might lower the risk of heart diseases.The study looked at a smaller group of fewer than 700 people.The researchers found that people who brushed less than twice a day for less than two minutes were three times more at risk,compared to those who brushed at least twice a day for two minutes.To have good mouth health,the American Dental Association also advises people to brush their teeth twice a day for two minutes each time,clean between their teeth once each day,keep a healthy diet,and see a dentist regularly.27.What's the main finding of the first study ?______A. cleaning your teeth often makes your heart have no problems.B. people usually develop heart diseases as they get older and older.C. a person has a lower risk for heart failure than for atrial fibrillation.D. keeping your teeth clean and fit can cut down your risk for heart problems.28.How did the author describe the two studies in the passage?______A. By giving facts.B. By listing numbers.C. By studying information.D. By explaining reasons.29.Why was the second study by the American Heart Association mentioned in the passage?______A. To prove some results of the first study were believable.B. To explain why not cleaning teeth causes heart problems.C. To remind us how long we spend brushing teeth each time.D. To provide people with some good advice on mouth health.30.Which of the following could be the best title for the passage?______A. Taking Care of Your Teeth Is Healthy for Your Heart.B. Heart Diseases Have Everything to Do with Teeth Health.C. We're Supposed to Do Something to Prevent Heart Diseases.D. Here Are Some Important Methods to Have Good Mouth Health.三、信息匹配(本大题共5小题,共10.0分)(2021·浙江省杭州市·模拟题)People who remember other people's names enjoy a huge advantage.They may become the most popular person simply by recalling people's names and introducing them to each other.(1)______ Improving your memory,in any field,begins with one simple rule:paying attention.When you want to remember a new person's name,you have to listen when he says it.Forget for a moment what you want to say and simply listen.(2)______ Pretend you don't hear the name clearly and repeat it, "You said your name is John." Or you may say it out loudly when you shake hands.Try to use the name several times in conversation like "What do you think about this,John?" or "See you,John".(3)______ Imagine John Smith's name is written on his forehead.This may seem childish (孩子气的),but the more unusual the picture we see,the better we recall it.(4)______ Look for a special feature(特征)of the person,like a long face or big eyes.Next time you meet this familiar person,you will remember his name.(5)______ Imagine the person standing in front of you as a famous person with the same name and you will remember his name.And then you have it-the secret of your amazing memory.31. A. A B. B C. C D. D E.E F. F32. A. A B. B C. C D. D E.E F. F33. A. A B. B C. C D. D E.E F. F34. A. A B. B C. C D. D E.E F. F35. A. A B. B C. C D. D E.E F. F四、阅读填空(本大题共1小题,共10.0分)36.(2021·浙江省杭州市·模拟题)In Chinese lunar Calendar,people divide the year into 24solar terms(节气).Start of Summer means the (1)______ (come)of a new season--summer.The temperature will rise (2)______ (quick)during this period.Here are three things about (3)______ Chinese greet the Start of Summer.✱Checking One's weightThe custom of weighing people at the Start of Summer (4)______ (start)from the Three Kingdoms Period and is still popular in South China today.It is said that thispractice will bring health and good luck to (5)______ (they).✱Eating (6)______ (egg)In ancient China,people believed (7)______ round egg was a symbol of a happy life and eating eggs on the day of Start of Summer was a good wish (8)______ goodhealth.People put leftover tea into boiled water together with eggs (9)______ (create)"tea eggs".Today it has become a local snack in many places of China.✱Taking care of the heartAccording to Chinese traditional medicine,Start of Summer is a key time to moisten of theheart. (10)______ it gets hot,heat can affect human health.So people prefer food such as fruit and vegetables rich in vitamins and cool in nature.五、单词拼写-单句(本大题共10小题,共10.0分)37.(2021·浙江省杭州市·模拟题)Thursday is the f ______ day of a week in westerncountries.38.(2021·浙江省杭州市·模拟题)If people could go to work by bus or by bike instead of caror motorbike,it would be helpful in fighting a ______ pollution.39.(2021·浙江省杭州市·模拟题)She won first prize in the game, t ______ none of us hadexpected it.40.(2021·浙江省杭州市·模拟题)She used to have long c ______ hair,but now she is used tokeeping her hair straight and short.41.(2021·浙江省杭州市·模拟题)You'd better take your umbrella with you.There is toomuch r ______ these days.42.(2021·浙江省杭州市·模拟题)How loudly you are talking!You've w ______ up thesleeping baby now.43.(2021·浙江省杭州市·模拟题)Linda enjoys dancing. It is one of her h ______ .44.(2021·浙江省杭州市·模拟题)For example,bike sharing is not new i ______ ,but Chinahas made it much more convenient.45.(2021·浙江省杭州市·模拟题)"I don't quite understand you,could you say it again ?"she said as p ______ as she could.46.(2021·浙江省杭州市·模拟题)The prime minister took a plane and f ______ to New Yorktoday for a three-day visit.六、书面表达(本大题共1小题,共15.0分)47.(2021·浙江省杭州市·模拟题)假如你是李华,你和家人想要到杭州旅行一周。

浙江省杭州市萧山区高桥初级中学2023-2024学年八年级下学期期中数学试题

浙江省杭州市萧山区高桥初级中学2023-2024学年八年级下学期期中数学试题

浙江省杭州市萧山区高桥初级中学2023-2024学年八年级下学期期中数学试题一、单选题1.下列方程中是一元二次方程的是( )A .210x -=B .21y x +=C .210x +=D .11x x+= 2.用反证法证明“a >b ”时,应先假设( )A .a ≥bB .a ≤bC .a =bD .a <b3.下列选项中,属于最简二次根式的是( )A B C D 4.用公式法解一元二次方程237x x +=时,首先要确定a ,b ,c 的值,下列叙述中,正确的是( )A .3,1,7a b c ==-=B .3,1,7a b c ===-C .3,1,7a b c ==-=-D .3,1,7a b c === 5.下列运算正确的是( )AB .C .D 6.如图,ABCD Y 的对角线AC BD ,相交于点O ,点E ,F 分别是线段AO BO ,的中点.若12cm AC BD +=,OAB V的周长是10cm ,则EF 的长为( )A .5B .4C .2D .17.下表是某篮球队的年龄分布,对于不同的x 值,下列关于年龄的数据量不会发生改变的是( )A .平均数、中位数B .中位数、众数C .中位数、方差D .平均数、方差8.某农户,用26m 长的篱笆围成一个一边靠住房墙(墙长12m ),且面积为280m 的长方形花园,垂直于住房墙的一条边留有一个1m 宽的门,设垂直于住房墙的另一条边的边长为m x ,如图所示,若可列方程为80x ⨯=★,则★表示的是( )A .(262)x -B .(272)x -C .262x -D .272x - 9.如图,在ABCD Y 中,57BCD ∠=︒,E ,F 是对角线AC 上两点,DF AD ⊥,AE EF CD ==,则ADE ∠的度数为( )A .19°B .29°C .38°D .43°10.关于x 的一元二次方程20x mx n ++=,下列说法:①若21m n -=,则方程一定有两个不相等的实数根;②若220m n -<,则方程没有实数根;③若n 是方程20x mx n ++=的一个根,则1m n +=-;④若()0=≠x t t 是方程20x mx n ++=的一个根,则1x t=是方程210nx mx ++= 的一个根.其中正确的是( )A .①②③④B .①③C .②④D .①②④二、填空题11x 的取值范围是12.甲、乙两人在相同情况下各打靶8次,每次打靶的成绩如图所示,统计两人成绩的方差为2S 甲,2S 乙,则2S 甲2S 乙填“>”或“<”).13.若一个多边形的内角和的14比一个五边形的内角和多90︒,那么这个多边形的边数是. 14.若2x =是关于x 的方程26mx nx -=-的解,则20242m n -+的值为.15.定义:不超过实数x 的最大整数称为x 的整数部分,记作[]x ,又把[]x x -称为x 的小数部分,记作{}x ,则有[]{}x x x =+.如:[2.3]2=,{2.3}0.3=,2.3[2.3]{2.3}=+;[ 2.3]3-=-,{2.3}0.7-=, 2.3[ 2.3]{2.3}-=-+-,若23x <<且{}x x =16.ABCD Y 中,若4AB =,AD m =,60A ∠=︒,将A B C D Y 沿某直线翻折,使得点A 与CD 的中点F 重合,若折痕与直线AD 交于点E ,1DE =,则m 的值为.三、解答题17.解方程:(1)230x x -=.(2)()23x x +=.18.已知x y =()23x y ++的值.19.如图,在55⨯的方格纸中,每个小正方形的边长均为1,A ,B 两点均在小正方形的顶点上,请按下列要求,在图1,图2中画顶点均在格点的四边形.(1)在图1中画一个面积为4的ABCD Y(2)在图2中画一个有一条对角线长等于3的平行四边形.20.某学校学生的数学期末总评成绩由开学考试成绩、期中考试成绩、期末考试成绩三部分组成.小明与小红三项得分如表(单位:分):(1)将表格中空缺的数据补充完整.(2)如果学校认为这三个项目的重要程度有所不同,而给予“期末考试”,“期中考试”,“开学考试”三个项目在期末总评成绩中所占的比例分别为50%,30%,20%,那么谁的最终成绩更高?请说明理由.21.如图,在ABCD Y 中,E 是BC 边上的一点,连接DE 并延长,与AB 的延长线相交于点F .(1)若E 是BC 的中点,求证:AB BF =;(2)若DE BC ⊥于点E ,3ABC EDC ∠=∠,且2EF CE =,4AB =,求AB 与CD 的距离. 22.某老牌造车企业为实现企业绿色低碳发展,通过技术改造升级,使新能源汽车项目的生产规模不断扩大,该企业9月,10月一共生产新能源汽车95000辆,其中10月份新能源汽车产量是9月份的1.2倍少4000辆.(说明:生产的新能源汽车全部销售出去).(1)求9月,10月新能源汽车产量各是多少辆(2)若10月份每辆新能源汽车的利润为1万元,11月份新能源汽车产量比上月增加%m ,11月份每辆新能源汽车的利润比上月增加%2m ,则11月份新能源汽车总利润达到66000万元,求m 的值.23.我们已经学习了利用配方法解一元二次方程,其实配方法还有其他重要应用.例如:已知x 可取任何实数,试求二次三项式223x x ++的最小值.解:()2222321212x x x x x ++=+++=++;∵无论x 取何实数,都有()210x +≥,∴()2122x ++≥,即223x x ++的最小值为2.【尝试应用】(1)请直接写出2289x x ++的最小值;【拓展应用】(2)试说明:无论x【创新应用】(3)如图,在四边形ABCD 中,AC BD ⊥,若20AC BD +=,求四边形ABCD 的面积最大值.24.已知ABCD Y 中,一动点P 在AD 边上,以每秒1cm 的速度从点A 向点D 运动.(1)如图1,运动过程中,若BP 平分ABC ∠,且满足AB BP =,求ABC ∠的度数.(2)如图2,另一动点Q 在BC 边上,以每秒4cm 的速度从点C 出发,在BC 间往返运动,两个点同时出发,当点P 停止运动时Q 点也停止,设运动时间为(0)t t >,若12cm AD =,当t 为多少秒时,以P 、D 、Q 、B 为顶点的四边形是平行四边形.(3)在(1)的条件下,连结CP 并延长,与AB 的延长线交于点F ,连结DF ,若CD =,直接写出:DPF V 的面积为.。

浙江省杭州市高桥初中教育集团2021届九年级语文下学期第二次质量检测试题

浙江省杭州市高桥初中教育集团2021届九年级语文下学期第二次质量检测试题

高桥初中教育集团2021学年第二学期第二次质量检测九年级语文试题卷一、基础知识及运用(30分)1.找出给加点字注音中正确的一项(3分)那一个个日子,都会在微露的晨曦中悄.然而至,在绽.放的晚霞里飘然归去。

我们在希望的早晨里遨游书海,我们在躁动的青春中释放激情。

闻着文字间流淌着的水墨香,我们将穿越六月深邃.的天空,去倾.听灵魂深处的声音。

A.qiāo diàn shuì qīnB.qiǎo diàn suì qīngc.qiāo zhàn shuì qīn D.qiǎo zhàn suì qīng2.下列各句中,没有错别字的一项是(3分)A.不久,第一阵鹤群映入眼帘,南侧蜿蜒群山的苍穹深处,浮现出一排黑芝麻粒般的小斑点,清晰可辩。

B.上课铃声过后,他才慌慌张张地冲进教室,“报告”声刚落,同学们轰堂大笑,原来他衣服的纽扣错位了。

C.毋庸讳言,得过且过、敷衍塞责的教师确实存在,但像“最美女教师”张丽莉那样爱生如子、恪尽职守的人,才是教师队伍中的主流。

D.王军填写从小学开始酷爱写诗,到目前为止,他已经写了200多首诗歌,同学亲切地称赞他为“小诗人”,用这个雅号叫他真是恰如其份了。

3.下列句子中加点的词语使用恰当的一项是(3分)A. 新年联欢晚会上,同学们载歌载舞,大家都沉湎..在欢快、热烈的气氛中。

C.许多网友转载了《用微波炉烹调食物会致癌》的文章,专家指出,这种骇人听闻....的传言没有科学依据,微波炉加热与常规加热对食物的影响基本相同。

D.初中生活快结束了,同学们面临分别,恋恋不舍,大家希望能萍水相逢....在新的校园里。

4.下列句子中没有语病的一句是(3分)A.纪录片《舌尖上的中国》不仅引发了人们对“文化认同”和“软实力输出”的思考,而且让人怀念童年时的美味。

B. 在与阿汤哥的对话中,马云表示自己被认为是长得最丑最奇特的人,这就是为什么我每次看见帅哥总是很嫉妒,但我从来没有嫉妒过他,他实在是太棒了,成功地扮演了这么多部精彩的电影。

2021年浙江省杭州市萧山区高桥初中教育集团中考化学质检试卷(附答案详解)

2021年浙江省杭州市萧山区高桥初中教育集团中考化学质检试卷(附答案详解)

2021年浙江省杭州市萧山区高桥初中教育集团中考化学质检试卷一、单选题(本大题共6小题,共18.0分)1. 分析下列实验操作正确的是( ) A. 稀释浓硫酸 B. 称量氢氧化钠固体 C. 测定溶液的pH D. a 处进气收集H 22. 二氧化碳和氢气可在一定条件下反应,生成一种重要的化工原料甲醇:CO 2+3H 2− 钌−膦鉻合物 加压CH 3OH +H 2O.下列有关该反应的说法正确的是( )A. 为CO 2的利用创造了一种新途径B. 钌−膦铬合物的质量在反应前后发生了变化C. 氢原子数在反应前后发生了改变D. 属于复分解反应3. 下列各项实验,能达到实验目的的是( )A. 用加入适量氯化钡溶液、再过滤的方法,除去硝酸钠溶液中的硫酸钠B. 用加足量水溶解、过滤、蒸发结晶的方法,除去 MnO 2固体中的KClC. 用过量盐酸溶液,验证暴露在空气中的氢氧化钠粉末是否变质D. 用含有稀硝酸的硝酸银溶液,鉴别硫酸钠溶液与氯化钠溶液4.在室温下,小乐完成了如下实验,若固体A(不含结晶水)溶于水既不吸热,也不放热,且实验过程中,不考虑水的蒸发。

则下列说法正确的是()A. 在室温下,溶液①为饱和溶液B. 在t℃时,A的溶解度一定为50克C. 溶液②和溶液④的溶质质量分数相同D. 溶液③和溶液④的溶液质量相同5.下列实验方案中,实验操作合理的是()选项实验目的实验操作A验证二氧化碳能与水反应生成碳酸向收集满二氧化碳的集气瓶中加入约13体积的滴有酚酞的水,振荡B检验氢氧化钠溶液已部分变质取少量溶液,滴加足量的氯化钡溶液,过滤,向滤液中滴加酚酞溶液C探究稀硫酸与氢氧化钠溶液是否完全反应向反应后所得的溶液中滴加硝酸银溶液D除去CO2中的SO2气体和水蒸气将混合气体依次通过NaOH溶液和浓硫酸A. AB. BC. CD. D6.下列图象中相关量的变化趋势与对应的实验过程不相符的是()A. 向一定量的氢氧化钠溶液中加入稀盐酸B. 加热一定质量的高锰酸钾固体C. 将等质量的铁和锌加入到足量的稀硫酸中D. 向一定量的稀盐酸中加入大理石二、填空题(本大题共1小题,共4.0分)7.有水(H2O)、双氧水(H2O2)、重水(D2O,“D”表示原子核中有一个质子和一个中子的氢原子)三种物质,从物质组成的角度看,这三种物质所含的元素共有______种,从化学性质的角度看,______与水的化学性质有较大的差异.三、简答题(本大题共1小题,共4.0分)8.一定质量的铁粉和铜粉的混合物,将其分为两等份,一份与足量的稀硫酸充分反应,产生氢气0.2g;另一份与足量的硫酸铜充分反应,经过滤、烘干,得固体10.8g。

2020-2021学年浙江省杭州市萧山区城区六校七年级(下)期中数学试卷(含解析)

2020-2021学年浙江省杭州市萧山区城区六校七年级(下)期中数学试卷(含解析)

2020-2021学年浙江省杭州市萧山区城区六校七年级(下)期中数学试卷一、选择题(共10小题).1.一种花粉颗粒直径约为0.0000065米,数字0.0000065用科学记数法表示为()A.0.65×10﹣5B.65×10﹣7C.6.5×10﹣6D.6.5×10﹣52.如图,∠1和∠2属于同位角的有()A.①②③B.②③④C.③④⑤D.①②⑤3.如图所示,下列条件能判断a∥b的有()A.∠1+∠2=180°B.∠2=∠4C.∠2+∠3=180°D.∠1=∠34.下列计算中,错误的是()A.(a2)3÷a4=a2B.C.(a﹣b)(﹣a+b)=﹣a2﹣b2D.(x﹣1)(x+3)=x2+2x﹣35.如果(2a m b m+n)3=8a9b15成立,则()A.m=3,n=2B.m=2,n=3C.m=2,n=5D.m=6,n=2 6.某地响应国家号召,实施退耕还林政策.退耕还林之前,该地的林地面积和耕地面积共有180km2.退耕还林之后,该地的耕地面积是林地面积的30%.设退耕还林之后该地的耕地面积为xkm2,林地面积为ykm2,则可列方程组()A.B.C.D.7.已知直线m∥n,将一块含30°角的直角三角板ABC按如图方式放置(∠ABC=30°),其中A,B两点分别落在直线m,n上,若∠1=20°,则∠2的度数为()A.20°B.30°C.45°D.50°8.若3y﹣2x+2=0,则9x÷27y的值为()A.9B.﹣9C.D.9.已知关于x,y的方程组,将此方程组的两个方程左右两边分别对应相加,得到一个新的方程,当m每取一个值时,就有一个方程,这些方程有一个公共解,这个公共解为()A.B.C.D.10.在象棋中,“兵”在过河后,可以向左、向右或往前行进一步,但是永远不能往后方移动.如图,“兵”已经过河了,可以向右、向上行进.那么“兵”从现在的位置走到“将”的位置,且要使路程之和最短,有几种行走的路线()A.16B.20C.24D.32二、填空题(每小题4分,共24分)11.(a﹣2b)2=.12.已知方程3x+2y=4,用含x的式子表示y为.13.已知(x﹣9)与(x+p)的乘积中不含x的一次项,则常数p的值为.14.在直角三角形ABC中,AB=8,将直角三角形ABC沿BC所在直线向右平移6个单位可以得到直角三角形DEF,此时,EG=3,则图中阴影部分的面积是.15.已知两个角∠1与∠2的两边分别平行,∠1比∠2的3倍少20度,则∠1的度数是度.16.已知的解是,求的解为.三、解答题(本题7大题,共66分)17.计算或化简:(1);(2)(﹣2a2)3+3a2•a4.18.解下列方程组:(1);(2).19.在正方形网格中,每个小正方形的边长均为1个单位长度,△ABC的三个顶点A,B,C都在格点(正方形网格的交点称为格点).现将△ABC平移,使点A平移到点D,点E,F分别是B,C的对应点.(1)在图中请画出平移后的△DEF;(2)△DEF的面积为.(3)在网格中画出一个格点P,使得S△BCP=S△DEF.(画出一个即可)20.两个边长分别为a和b的正方形如图放置,其未叠合部分(阴影)面积为S1,若再在图1中大正方形的右下角摆放一个边上为b的小正方形(如图2),两个小正方形叠合部分(阴影)面积S2.(1)用含a,b的代数式分别表示S1,S2;(2)若a+b=15,ab=5,求S1+S2的值;(3)当S1+S2=64时,求出图3中阴影部分的面积S3.21.如图,长方形ABCD中,AD∥BC,E为边BC上一点,将长方形沿AE折叠(AE为折痕),使点B与点F重合,EG平分∠CEF交CD于点G,过点G作HG⊥EG交AD于点H.(1)请判断HG与AE的位置关系,并说明理由.(2)若∠CEG=20°,请利用平行线相关知识求∠DHG的度数.22.某场足球赛,价格为成人票50元/张,儿童票20元/张;门票总收入为7700元.(1)若售票总数160张,求售出的成人票张数.(2)设售出门票总数a张,其中儿童票b张.①求a,b满足什么数量关系;②若售出的门票中成人票比儿童票的7倍还多6张,求b的值.23.如图,直线PQ∥MN,一副三角尺(∠ABC=∠CDE=90°,∠ACB=30°,∠BAC=60°,∠DCE=∠DEC=45°)按如图①放置,其中点E在直线PQ上,点B,C均在直线MN上,且CE平分∠ACN.(1)求∠DEQ的度数.(2)如图②,若将三角形ABC绕点B以每秒3度的速度按逆时针方向旋转(A,C的对应点分别为F,G),设旋转时间为t(s)(0≤t≤60).①在旋转过程中,若边BG∥CD,求t的值.②若在三角形ABC绕点B旋转的同时,三角形CDE绕点E以每秒2度的速度按顺时针方向旋转(C,D的对应点为H,K).请直接写出当边BG∥HK时t的值.参考答案一、选择题(共10小题).1.一种花粉颗粒直径约为0.0000065米,数字0.0000065用科学记数法表示为()A.0.65×10﹣5B.65×10﹣7C.6.5×10﹣6D.6.5×10﹣5解:数字0.0000065用科学记数法表示为6.5×10﹣6.故选:C.2.如图,∠1和∠2属于同位角的有()A.①②③B.②③④C.③④⑤D.①②⑤解:①、∠1和∠2是同位角,故此选项符合题意;②、∠1和∠2是同位角,故此选项符合题意;③、∠1和∠2不是同位角,故此选项不合题意;④、∠1和∠2不是同位角,故此选项不合题意;⑤、∠1和∠2是同位角,故此选项符合题意;故选:D.3.如图所示,下列条件能判断a∥b的有()A.∠1+∠2=180°B.∠2=∠4C.∠2+∠3=180°D.∠1=∠3解:A、∵∠1+∠2=180°,不能判定a∥b,错误;B、∵∠2=∠4,∴a∥b,正确;C、∵∠2+∠3=180°,不能判定a∥b,错误;D、∵∠1=∠3,不能判定a∥b,错误;故选:B.4.下列计算中,错误的是()A.(a2)3÷a4=a2B.C.(a﹣b)(﹣a+b)=﹣a2﹣b2D.(x﹣1)(x+3)=x2+2x﹣3解:A、原式=a6÷a4=a2,故A正确.B、原式=x2•(﹣2x)=5x3,故B正确.C、原式=﹣(a﹣b)(a﹣b)=﹣a2+2ab﹣b2,故C错误.D、原式=x2+2x﹣3,故D正确.故选:C.5.如果(2a m b m+n)3=8a9b15成立,则()A.m=3,n=2B.m=2,n=3C.m=2,n=5D.m=6,n=2【分析】逆向运用积的乘方运算法则求解即可.解:∵(2a m b m+n)3=8a9b15,∴3m=9,3(m+n)=15,解得m=3,n=2,故选:A.6.某地响应国家号召,实施退耕还林政策.退耕还林之前,该地的林地面积和耕地面积共有180km2.退耕还林之后,该地的耕地面积是林地面积的30%.设退耕还林之后该地的耕地面积为xkm2,林地面积为ykm2,则可列方程组()A.B.C.D.解:设耕地面积x平方千米,林地面积为y平方千米,根据题意列方程组.故选:B.7.已知直线m∥n,将一块含30°角的直角三角板ABC按如图方式放置(∠ABC=30°),其中A,B两点分别落在直线m,n上,若∠1=20°,则∠2的度数为()A.20°B.30°C.45°D.50°解:∵直线m∥n,∴∠2=∠ABC+∠1=30°+20°=50°,故选:D.8.若3y﹣2x+2=0,则9x÷27y的值为()A.9B.﹣9C.D.解:∵3y﹣2x+2=0,∴3y﹣2x=﹣2,∴2x﹣3y=2,则9x÷27y=32x÷33y=32x﹣3y=32=9.故选:A.9.已知关于x,y的方程组,将此方程组的两个方程左右两边分别对应相加,得到一个新的方程,当m每取一个值时,就有一个方程,这些方程有一个公共解,这个公共解为()A.B.C.D.【分析】根据题意①+②得x﹣y﹣9+m(x+y﹣1)=0,然后根据题意列出方程组即可求得公共解.解:①+②得,x+my+mx﹣y=9+mx﹣y﹣9+mx+my﹣m=0x﹣y﹣9+m(x+y﹣1)=0根据题意,这些方程有一个公共解,与m的取值无关,解得所以这个公共解为故选:C.10.在象棋中,“兵”在过河后,可以向左、向右或往前行进一步,但是永远不能往后方移动.如图,“兵”已经过河了,可以向右、向上行进.那么“兵”从现在的位置走到“将”的位置,且要使路程之和最短,有几种行走的路线()A.16B.20C.24D.32解:“兵”从现在的位置走到“将”的位置,总共会走3次右和3次上,则行走的路线的种数有:==20.故选:B.二、填空题(每小题4分,共24分)11.(a﹣2b)2=a2﹣4ab+4b2.解:(a﹣2b)2=a2﹣4ab+4b2.故本题答案为:a2﹣4ab+4b2.12.已知方程3x+2y=4,用含x的式子表示y为y=.解:3x+2y=4,2y=4﹣3x,解得:y=.故答案为:y=.13.已知(x﹣9)与(x+p)的乘积中不含x的一次项,则常数p的值为9.【分析】根据多项式乘以多项式法则把两式相乘,让一次项系数为0列式求解即可.解:(x﹣9)(x+p)=x2+px﹣9x﹣9p=x2+(p﹣9)x﹣9p,由题意可得,p﹣9=0,解得p=9.故答案为:9.14.在直角三角形ABC中,AB=8,将直角三角形ABC沿BC所在直线向右平移6个单位可以得到直角三角形DEF,此时,EG=3,则图中阴影部分的面积是39.解:根据平移的性质得到:阴影部分的面积等于梯形ABDG的面积,所以图中阴影部分的面积是:(8﹣3+8)×6=39.即:图中的阴影部分的面积为39.故答案是:39.15.已知两个角∠1与∠2的两边分别平行,∠1比∠2的3倍少20度,则∠1的度数是10或130度.解:①当∠1=∠2时,∵∠1=3∠2﹣20°,∴∠1=3∠1﹣20°,解得∠1=10°;②当∠1+∠2=180°时,∵∠1=3∠2﹣20°,∴∠2+3∠2﹣20°=180°,解得∠2=50°,∴∠1=180°﹣∠2=130°;故答案为:10或130.16.已知的解是,求的解为.解:把代入方程组得:,方程同时×5,得:,∴方程组的解为.故答案为:.三、解答题(本题7大题,共66分)17.计算或化简:(1);(2)(﹣2a2)3+3a2•a4.解:(1)原式=3﹣1+4=6;(2)原式=﹣8a6+3a6=﹣5a6.18.解下列方程组:(1);(2).解:(1)①×2+②得,7a=21,解得a=3,将a=3代入①,得b=﹣2,故原方程组的解是:;(2)化简①得,3x+2y=7③,②×2﹣③得,﹣x=1,解得,x=﹣1,将x=3代入②得,y=5,故原方程组的解是;.19.在正方形网格中,每个小正方形的边长均为1个单位长度,△ABC的三个顶点A,B,C都在格点(正方形网格的交点称为格点).现将△ABC平移,使点A平移到点D,点E,F分别是B,C的对应点.(1)在图中请画出平移后的△DEF;(2)△DEF的面积为7.(3)在网格中画出一个格点P,使得S△BCP=S△DEF.(画出一个即可)解:(1)如图所示,△DEF即为所求;(2)△DEF的面积为:4×4﹣×2×3﹣×1×4﹣×2×4=7;故答案为:7;(3)如图所示,点P即为所求(答案不唯一).20.两个边长分别为a和b的正方形如图放置,其未叠合部分(阴影)面积为S1,若再在图1中大正方形的右下角摆放一个边上为b的小正方形(如图2),两个小正方形叠合部分(阴影)面积S2.(1)用含a,b的代数式分别表示S1,S2;(2)若a+b=15,ab=5,求S1+S2的值;(3)当S1+S2=64时,求出图3中阴影部分的面积S3.【解答】(1)由图可得,S1=a2﹣b2S2=a2﹣a(a﹣b)﹣b(a﹣b)﹣b(a﹣b)=2b2﹣ab.(2)S1+S2=a2﹣b2+2b2﹣ab=a2+b2﹣ab.∵a+b=15,ab=5,∴S1+S2=a2+b2﹣ab=(a+b)2﹣3ab=225﹣3×5=210.(3)由图可得,∵S1+S2=a2+b2﹣ab=64,∴.21.如图,长方形ABCD中,AD∥BC,E为边BC上一点,将长方形沿AE折叠(AE为折痕),使点B与点F重合,EG平分∠CEF交CD于点G,过点G作HG⊥EG交AD于点H.(1)请判断HG与AE的位置关系,并说明理由.(2)若∠CEG=20°,请利用平行线相关知识求∠DHG的度数.解:(1)平行,理由如下:∵长方形沿AE折叠,∴∠AEB=∠AEF,∵EG平分∠CEF交CD于点G,∴∠FEG=∠CEG,∵∠AEB+∠AEF+∠FEG+∠CEG=180°,∴∠AEG=∠AEF+∠FEG=90°,∴AE⊥EG,∵HG⊥ED,∴HG∥AE;(2)∵∠CEG=20°,∴∠AEB=70°,∵长方形ABCD中,AD∥BC,∴∠AEB=∠DAE=70°,∵HG∥AE,∴∠DHG=∠DAE=70°.22.某场足球赛,价格为成人票50元/张,儿童票20元/张;门票总收入为7700元.(1)若售票总数160张,求售出的成人票张数.(2)设售出门票总数a张,其中儿童票b张.①求a,b满足什么数量关系;②若售出的门票中成人票比儿童票的7倍还多6张,求b的值.解:(1)设成人票售出x张,则儿童票售出(160﹣x)张,依题意得:50x+20(160﹣x)=7700,解得:x=150.答:成人票售出150张.(2)①依题意得:成人票售出(a﹣b)张,∴50(a﹣b)+20b=7700,∴50a﹣30b=7700,∴a与b关系为:5a﹣3b=770.②依题意得:成人票售出(a﹣b)张,∴a﹣b=7b+6则a﹣8b=6,又∵5a﹣3b=770,∴解得:.∴b的值为20.23.如图,直线PQ∥MN,一副三角尺(∠ABC=∠CDE=90°,∠ACB=30°,∠BAC=60°,∠DCE=∠DEC=45°)按如图①放置,其中点E在直线PQ上,点B,C均在直线MN上,且CE平分∠ACN.(1)求∠DEQ的度数.(2)如图②,若将三角形ABC绕点B以每秒3度的速度按逆时针方向旋转(A,C的对应点分别为F,G),设旋转时间为t(s)(0≤t≤60).①在旋转过程中,若边BG∥CD,求t的值.②若在三角形ABC绕点B旋转的同时,三角形CDE绕点E以每秒2度的速度按顺时针方向旋转(C,D的对应点为H,K).请直接写出当边BG∥HK时t的值.解:(1)如图①中,∵∠ACB=30°,∴∠ACN=180°﹣∠ACB=150°,∵CE平分∠ACN,∴∠ECN=∠ACN=75°,∵PQ∥MN,∴∠QEC+∠ECN=180°,∴∠QEC=180°﹣75°=105°,∴∠DEQ=∠QEC﹣∠CED=105°﹣45°=60°.(2)①如图②中,∵BG∥CD,∴∠GBC=∠DCN,∵∠DCN=∠ECN﹣∠ECD=75°﹣45°=30°,∴∠GBC=30°,∴3t=30,∴t=10s.∴在旋转过程中,若边BG∥CD,t的值为10s.②如图③中,当BG∥HK时,延长KH交MN于R.∵BG∥KR,∴∠GBN=∠KRN,∵∠QEK=60°+2t,∠K=∠QEK+∠KRN,∴∠KRN=90°﹣(60°+2t)=30°﹣2t,∴3t=30°﹣2t,∴t=6s.如图③﹣1中,当BG∥HK时,延长HK交MN于R.∵BG∥KR,∴∠GBN+∠KRM=180°,∵∠QEK=60°+2t,∠EKR=∠PEK+∠KRM,∴∠KRM=90°﹣(180°﹣60°﹣2t)=2t﹣30°,∴3t+2t﹣30°=180°,∴t=42s.综上所述,满足条件的t的值为6s或42s.。

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5.如果你看过中央电视台体育频道的围棋讲座就会发现,棋子在竖直放置的棋盘上可以移动,但不会掉下来。原来,棋盘和棋子都是由磁性材料制成的。棋子不会掉落是因为( )
A.质量小,重力可以忽略不计
B.受到棋盘对它向上的摩擦力
C.棋盘对它有很大的吸引力
D.它一方面受到棋盘的吸引,另一方面还受到空气的浮力
6.如图是一些研究电现象和磁现象的实验。下列关于这些实验的叙述正确的是()
C.这种氧原子的核内质子数为10
D.这种氧原子的核外电子数为10
19.如图甲所示是某人设计的振动发电装置,它由一个辐向形永久磁铁和一个套在辐向形永久磁铁槽中的线圈组成,磁场的磁感线均沿半径方向均匀分布(如图乙所示).外力推动线圈框架的P端,使线圈沿轴线做往复运动,便有电流通过灯珠。关于此发电装置,以下说法不正确的是()
A.红磷在空气中燃烧产生大白雾
B.蜡烛燃烧,可生成水和二氧化碳
C.熄灭蜡烛时产生白烟,用燃着的火柴取点白烟,蜡烛重新燃
D.碳在氧气中剧烈燃烧,火星四射,生成一种有刺激性气味的无色气体
15.如图所示,条形磁铁置于水平桌面上,电磁铁水平放置且左端固定。当电路中滑动变阻器的滑片P逐渐向左移动,条形磁铁仍然静止。在此过程中,条形磁铁受到的摩擦力()
C.该气体中可能含有C2H2
D.该气体不可能同时含有CH4、C2H2、C2H4
二、填空题
21.(1)将下列符号中“2”所表示的意义写在横线上:N2______ _____
(2)写出下列物质的化学式:高锰酸钾______,地壳含量最多的金属元素和非金属元素形成的化合物_____________。
22.现有①液氧 ②液态空气 ③冰水共存物 ④二氧化锰 ⑤石灰水 ⑥氯酸钾 ⑦过氧化氢溶液 ⑧水银。其中属于混合物的有(填序号)___;属于纯净物的有(填序号)___;
C.使用试电笔时,手指不能碰到笔尾金属体,以免发生触电事故
D.空气开关跳闸后,应立即合上
2.下列关于空气的说法中错误的是( )
A.空气是人类宝贵的自然资源
B.空气中的稀有气体常用作灭火剂
C.空气中的氮气常用作保护气
D.空气中的氧气主要来自于植物的光合作用
3.今年5月9日,由中国科学院等相关部门正式发布了113号、115号、117号、118号元素的中文名称。下表是这四种元素的部分信息,以下有关说法正确的是()
23.在分子、原子、质子、中子、电子、原子核、阳离子、阴离子这些粒子中:
A.逐渐增大,方向向右
B.逐渐减小,方向向右
C.逐渐增大,方向向左
D.逐渐减小,方向向左
16.关于直流电动机的电流,下列说法中正确的是( )
A.线圈中电流是直流,外部电路也是直流
B.线圈中电流是交流,外部电路也是交流
C.线圈中电流是直流,外部电路是交流
D.线圈中电流是交流,外部电路是直流
17.核外电子数相同,核内质子数不同的两种粒子,它们可能是()
原子序数
中文名称
符号
汉语拼音
113

Nh

115


117
Ts
tián
118
Og
ào
A.鉨属于金属元素
B.镆的元素符号是mo
C. 元素的相对原子质量是117
D. 元素在自然界中含量丰富
4.某物质的分子式为HnRO2n-1,它的相对分子质量是m,则R元素的相对原子质量是( )
A.m−3n−1B.m−3n+1C.m−33n−16D.m−33n+16
浙江省杭州市萧山区高桥初中教育集团【最新】第二学期期中考试质量检测科学试题
学校:___________姓名:___________班级:___________考号:___________
一、选择题
1.家庭电路中,下列操作符合要求的是()
A.输电线进户后,应先接电能表
B.家庭电路的开关,接在零线或火线上都可以
A.aB.b
C.cD.d
10.三聚磷酸钠(Na5P3O10)过去常用作洗衣粉的辅助剂,我国部分省市为防止水体富营养化已禁止销售和使用含磷洗衣粉.在Na5P3O10中磷元素的化合价为( )
A.+3B.+4C.+5D.+6
11.如图表示两盏白炽灯和两只插座的安装电路图,其中一项安装错误的是( )
A.插座CB.插座DC.A灯及开关D.B灯及开关
①一种元素的原子和另一种元素的离子②同种元素的原子和离子③两种不同元素的原子④两种不同元素的离子。
A.①③B.①④C.②③D.③④
18.我国在1993年成功制取了一种由相对原子质量为18、核电荷数为8的氧原子构成的双原子分子气体,下列说法正确的是( )
A.这种气体的相对分子质量是36克
B.这种氧原子和氢原子构成的水分子,其相对分子质量为20
A.图甲中小磁针被铁棒吸引,说明铁棒本身具有磁性
B.图乙中小磁针发生偏转,说明电流周围存在磁场
C.图丙中条形磁铁静止时A端总是指向北方,说明A端是条形磁铁的南极
D.图丁中铁钉B吸引的大头针比A多,说明电磁铁的磁性强弱与电流大小有关
7.下列有关氧气的说法中,正确的是( )
A.通常状况下,氧气极易溶于水
B.把带火星的木条伸入集气瓶中验满
C.氧气具有可燃性,可用作燃料
D.用高锰酸钾制取氧气属于分解反应
8.下列用微观图示表示的物质变化,属于化学变化的是( )
氢分子氧分子水分子A分子B分子钠离子氯离子氢氧根离子氢离子
A.①②B.②③C.①③D.①②③
9.卢瑟福的α粒子轰击金箔实验,推翻了汤姆森在 1903 年提出的原子结构模型,为建立现代原子理论打下了基础。如图线条中,不可能是α粒子(带正电)在该实验中的运动轨迹的是
12.如图所示,在条形磁铁的一端吸引着两个大头针的针尖部,则这两个大头针的针帽将()
A.互相排斥B.互相吸引C.既不排斥也不吸引D.无法确定
13.某元素R的相对原子质量为a,其固体单质0.2ag与4.8g氧气完全化合生成RxOy,则x、y的数值分别是( )
A.1、2B.2、3C.3、4D.2、1
14.下列现象描述正确的是( )
A.该装置是利用电磁感应原理制成的B.该装置是将机械能转化为电能
C.小灯珠中流过的电流是直流电D.小灯珠中流过的电流是交流电
20.某气体是C2H4、C2H2、CH4中的一种或几种组成,测得其中碳元素和氢元素的质量比为6:1,下列对该气体组成判断正确的是( )
A.该气体中一定含有C2H2
B.该气体中一定没有CH4
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