nêu thông tin của chu văn an ?
9. Complete the sentences with the words from the box.high-speed drive eco-friendly rides fly pilotless solar-powered pedaled 1. The plane into Trinity Bay and broke apart. 2. We’ll see __________________planes or autonomous planes in the next 40 to 50 years3.A_______________only run efficiently when the sun shines.4. Driving a(n)______________________vehicle is a great wa...
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9. Complete the sentences with the words from the box.
high-speed drive eco-friendly rides fly pilotless solar-powered pedaled
1. The plane into Trinity Bay and broke apart.
2. We’ll see __________________planes or autonomous planes in the next 40 to 50 years
3.A_______________only run efficiently when the sun shines.
4. Driving a(n)______________________vehicle is a great way to help human health and the environment.
5. Cars that can _______________in the sky are coming sooner than you think.
6. Yesterday afternoon, we rented a swan boat and _______________________around the lake
7. The Shinkansen bullet train, a_________________passenger train of Japan, can reach a speed of 320km/h
8. My brother_____________________to school on his bicycle.
10. Complete the sentence with will and one the verbs in the box to make some prediction about the future
translate live take have fly stay control stop find recognise |
1. People __________________vacations on the Moon
2. Computers_____________________your voice and follow your commands
3. Talking computers________________________ English. You won’t have to study English
4. Robots___________________all the housework and take care of your family.
5. You_____________________to work in your flying car.
6. People __________the weather.
7. All students ___________________ at home to study on the Internet.
8. Scientists ______________________life on another planet.
9. Everyone __________________eating meat and is a vegetarian.
10. People________________________for 200 years.
XI. Write the correct possessive adjective or pronoun for these sentences.
1. This dessert is but you can have it. (I)
2.________________car is so dirty I can’t even tell what color it is. (you)
3. The cat is in a good mood. It’s just had breakfast, (it)
4. Mark and I did homework, but Jennifer didn’t do . (we/ she)
5. It wasn’t____________mistake, it was for getting the food order wrong. (I/ they)
6. She gave him_____________telephone number, and he gave her____________.(she/he)
7. I think__________________garden is bigger than_______________ (they/ we)
8. Is she a friend of__________________? ~ No. She is a cousin of________________ (you/I)
9.__________________car wasn’t working, so he used__________________(he/ she)
10._________________computer needs to be fixed, but___________________is working.(I/he)
9. Complete the sentences with the words from the box.
1. The plane flew into Trinity Bay and broke apart.
2. We'll see high-speed planes or autonomous planes in the next 40 to 50 years.
3. A solar-powered vehicle only runs efficiently when the sun shines.
4. Driving an eco-friendly vehicle is a great way to help human health and the environment.
5. Cars that can fly in the sky are coming sooner than you think.
6. Yesterday afternoon, we rented a swan boat and pedaled around the lake.
7. The Shinkansen bullet train, a high-speed passenger train of Japan, can reach a speed of 320km/h.
8. My brother rides to school on his bicycle.
10. Complete the sentence with will and one the verbs in the box to make some prediction about the future
1. People will take vacations on the Moon.
2. Computers will recognize your voice and follow your commands.
3. Talking computers will translate English. You won't have to study English.
4. Robots will control all the housework and take care of your family.
5. You will fly to work in your flying car.
6. People will find the weather.
7. All students will stay at home to study on the Internet.
8. Scientists will find life on another planet.
9. Everyone will stop eating meat and become a vegetarian.
10. People will live for 200 years.
XI. Write the correct possessive adjective or pronoun for these sentences.
1. This dessert is mine but you can have it.2. Your car is so dirty I can't even tell what color it is.
3. The cat is in a good mood. It's just had its breakfast.
4. Mark and I did our homework, but Jennifer didn't do hers.
5. It wasn't my mistake, it was theirs for getting the food order wrong.
6. She gave him her telephone number, and he gave her his.
7. I think their garden is bigger than ours.
8. Is she a friend of yours? ~ No. She is a cousin of mine.
9. His car wasn't working, so he used hers.
10. My computer needs to be fixed, but his is working.
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x/3=y/7=z/5 và x^2-y^2+z^2= -60
Ta có:
`x/3 = x^2/9 = y/7 = y^2/49 = z/5 = z^2/25`
Biết: `x^2 - y^2 + z^2 = -60`
Áp dụng tính chất của dãy tỉ số bằng nhau, ta có:
`x/3 = x^2/9 = y/7 = y^2/49 = z/5 = z^2/25 = (x^2 - y^2 + z^2)/(9 - 49 + 25) = -60/-15 = 4`
`-> x/3 = 4 => x = 4 . 3 = 12`
`-> y/7 = 4 => y = 4 . 7 = 28`
`-> z/5 = 4 => z = 4 . 5 = 20`
Vậy: `x = 12 ; y = 28 ; z = 20`
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Sửa:
Ta có:
`x/3 = x^2/9 = y/7 = y^2/49 = z/5 = z^2/25`
Biết: `x^2 - y^2 + z^2 = -60`
Áp dụng tính chất của dãy tỉ số bằng nhau, ta có:
`x/3 = x^2/9 = y/7 = y^2/49 = z/5 = z^2/25 = (x^2 - y^2 + z^2)/(9 - 49 + 25) = -60/-15 = 4`
`-> x^2/9 = 4 => x^2 = 4 . 9 = 36 => x = +-6`
`-> y^2/49 = 4 => y^2 = 4 . 49 = 196 => y = +-13`
`-> z^2/25 = 4 => z^2 = 4 . 25 = 100 => z = +-10`
Vậy: `(x;y;z) = (6 ; 13 ; 10),(-6;-13;-10)`
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6. Complete the sentences with the words or phrases in the box.1. I learned to a bike when I was six2. David the taxi and gave the driver the address of his hotel3. “Are you going by train?” “No, I’m .”4. Tom the bus at the wrong bus top, so he walked from these to school.5. She has to thousan...
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6. Complete the sentences with the words or phrases in the box.
1. I learned to a bike when I was six
2. David the taxi and gave the driver the address of his hotel
3. “Are you going by train?” “No, I’m .”
4. Tom the bus at the wrong bus top, so he walked from these to school.
5. She has to thousands of miles every year for her job.
6. Cycling is my favourite form of .
7. Do you know how to fasten your ?
8. Wouldn’t it be quicker to go by ?
9. He managed to the boat between the rocks.
10. I was stuck in for an hour yesterday.
7. Complete the sentences with will or won’t.
1. In a few years everyone know how to use the Internet.
2. In the future people go to school or university. They study at home using their computer.
3. Some teachers are worried that computers take their jobs one day.
4. In a few years, everyone speak English.
5. Chinese become the global language in the near future; it is English as far as I know.
8. Complete the conversation with the correct form of the verb in brackets.
Linda: Do you want to go on holiday to Viet Nam with me?
Susan: I don’t know
Linda: Come on. We (1. have) a great time. We (2. eat) good food. We (3. meet) a lot of nice people. Your Vietnamese (4. get) better and we (5. not spend) a lot of money.
Susan: Well …
Linda: It (6. not rain) and we (7. go) to Ha Noi and we (8. buy) some cool clothes.
Susan: I think we (9. enjoy) beautiful landscapes in Viet Nam.
Linda: And we (10. try) pho and other traditional Viet Nam dishes.
14.
a, \(C_2H_4+Br_2\rightarrow C_2H_4Br_2\)
b, \(n_{C_2H_4Br_2}=\dfrac{9,4}{188}=0,05\left(mol\right)\)
Theo PT: \(n_{C_2H_4}=n_{C_2H_4Br_2}=0,05\left(mol\right)\)
\(\Rightarrow\left\{{}\begin{matrix}\%V_{C_2H_4}=\dfrac{0,05.22,4}{6,72}.100\%\approx16,67\%\\\%V_{CH_4}\approx83,33\%\end{matrix}\right.\)
15.
\(n_{CO_2}=\dfrac{0,66}{44}=0,015\left(mol\right)=n_C\)
\(n_{H_2O}=\dfrac{0,27}{18}=0,015\left(mol\right)\Rightarrow n_H=0,015.2=0,03\left(mol\right)\)
⇒ mC + mH = 0,015.12 + 0,03.1 = 0,21 (g) < mA
→ A gồm C, H và O.
⇒ mO = 0,45 - 0,21 = 0,24 (g)
\(\Rightarrow n_O=\dfrac{0,24}{16}=0,015\left(mol\right)\)
Gọi CTPT của A là CxHyOz.
⇒ x:y:z = 0,015:0,03:0,015 = 1:2:1
→ A có dạng (CH2O)n
Mà: MA = 30.6 = 180 (g/mol)
\(\Rightarrow n=\dfrac{180}{12+1.2+16}=6\)
→ A là C6H12O6
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bài 14:
a) CH4 + Br2 ------x----->
C2H4 + Br2----------->C2H4Br2
Mol: 0,05 <---0,05 <---------- 0,05
b) nC2H4Br2 = m/M=9,4/188=0,05 (mol)
VC2H4=n . 22,4 = 1,12(mol)
VCH4= 6,72 - 1,12=5,6(mol)
%VC2H4=VC2H4 . 100/6,72 =16,7 %
%VCH4= 100%-16,7%=83,3%
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Cho tam giác ABC vuông tại A có AB < AC, vẽ AH vuông góc BC. Trên tia đối của tia HA lấy điểm D sao cho HD = HA, trên tia HC lấy điểm E sao cho HE = HB. Biết rằng tam giác ACH = tam giác DCH, tam giác DEH = tam giác HAB. Chứng minh DE vuông góc AC
Ta có: \(n_{\left(CH_3COO\right)_2Mg}=\dfrac{0,71}{142}=0,005\left(mol\right)\)
PT: \(2CH_3COOH+Mg\rightarrow\left(CH_3COO\right)_2Mg+H_2\)
__________0,01_______________0,005______0,005 (mol)
a, \(C_{M_{CH_3COOH}}=\dfrac{0,01}{0,025}=0,4\left(M\right)\)
\(V_{H_2}=0,005.22,4=0,112\left(l\right)\)
b, \(CH_3COOH+NaOH\rightarrow CH_3COONa+H_2O\)
\(n_{NaOH}=n_{CH_3COOH}=0,01\left(mol\right)\)
\(\Rightarrow V_{NaOH}=\dfrac{0,01}{0,75}=\dfrac{1}{75}\left(l\right)=13,33\left(ml\right)\)
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3. Choose the correct answer.11.People won’t use flying cars____________ the year 2050. A. before B. after C. during D. until12.The city is facing serious____________problems. A. pollution B. polluted C. pollute D. pollutant13.We believe that urban transport pods can travel ____________around 30kph. A. with B. at C. in D. on14...
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3. Choose the correct answer.
11.People won’t use flying cars____________ the year 2050.
A. before B. after C. during D. until
12.The city is facing serious____________problems.
A. pollution B. polluted C. pollute D. pollutant
13.We believe that urban transport pods can travel ____________around 30kph.
A. with B. at C. in D. on
14.Do you think the__________price will increase next month?
A. fossil fuels B. gases C. fuel D. natural gases
15.We will use more___________ energy in the future.
A. solar B. sunny C. sun D. sunlight
16.A jet pack doesn’t ___ a lot of space.
A. have B. bring C. take D. occur
17.Which of transport do you think will be used in the future?
A. mean B. meaning C. meanings D. means
18.We are looking for types of vehicles that help us to avoid .
A. traffic B. traffic jam C. rush hours D. walking
19. I'm afraid I _______ able to attend your workshop tomorrow.
A. won't be B. isn't C. wasn't D. weren't
20. A _______ has two pedals.
A. ship B. car C. bicycle D. plane
21.I think we have electric taxis very soon.
A. may B. might C. will D. would
22.With teleportation, you disappear at a place, and then in another place seconds later.
A. appears B. appeared C. reappear D. reappears
23. _______ grandfather used to take us fishing.
A. Mine B. My C. Our D. Ours
24.My brother and I often come to school___________ foot.
A. at B. in C. by D. on
25. I really want to fly a _______ like Doraemon.
A. car B. bamboo-copter C. ship D. boat
26.The white cat is Helen’s, and the black cat is .
A. my B. I C. mine D. of mine
27.We try to make the future green by using vehicles or kinds of energy that are .
A. environmentally friendly B. environment friendly
C. environmentally friendship D. environmental friendly
28.This is Linda’s hat, and those shoes are .
A. her B. hers C. our D. their
29.It will be___________ to ride a jet pack in bad weather because it doesn’t have a roof.
A. enjoyable B. pleasant C. unpleasant D. comfortable
30.A sky safety system can help cars to___________ traffic jams and crashes.
A. avoid B. have C. use D. take
31. _______ is a single- wheel bike.
A. Bike B. Hover scooter C. Skytrain D. monowheel
32. A hyperloop helps everyone _______ traffic jams.
A. avoid B. use C. have D. take
33. Petrol- powered cars are not _________. They cause pollution.
A. eco- friendly B. simple C. easy to use D. comfortable
34. Bullet train is fast, green, and _________.
A. show B. fast C. safe D. unsafe
35. Lan bought _______ dress at the mall.
A. yours B. mine C. her D. hers
36. I often visit ___________ grandparents at the weekend..
A. it B. my C. mine D. hers
37. Id like you to meet Rita. She’s a great friend of .
A. us B. our C. ours D. me
38. The house is big, but windows are small.
A. it B. its C. it’s D.their
39. Sue fell down the stairs and broke leg.
A. her B. hers C. its D. his
40. Your travel planssound just as exciting as________________!
A. I B.me C.my D. mine
4. Choose the correct completion in the brackets.
1. Is this (your/ yours) pen?
2. Please give this dictionary to Mary. It’s (her/ hers) .
3. A: Don’t forget (your/ yours) hat. Here.
B: No, that’s not (my/ mine) hat. (My/ mine) is green.
4. A: Please take this wood carving as a present from me. Here you are. It’s (your/ yours)_______
B: Thank you.
5. A: Isn’t that the Smith’s car? That one over there. The blue one.
B: No, that’s not (their/ theirs) . (Their/ Theirs) car is dark blue.
5. Choose the correct completion in the brackets.
1. A: Nick really likes (his/ him) new bicycle. It is very light and fast. How do you like (your/ yours)
B: (My / mine) is cheap, but it’s very reliable.
2. A: Excuse me. Is this (your/ yours) umbrella?
B: I don’t have an umbrella. Ask Ken. Perhaps it is (him/ his) .
3. A: When do (your/ yours) classes begin?
B: September 2nd. How about (your/ yours) ? When do (your/ yours) begin?
A: (My/ Mine) begin on August 23rd.
4. A: Mary, (your/ yours) spaghetti sauce is delicious!
B: Thank you, but it’s not as good as (your/ yours) .
A: Oh, no. (Your/ Yours) is much better. It tastes as good as Anna’s
B: Do you like Anna’s spaghetti sauce? I think (her/ hers) is too salty.
A: Maybe. (My/ Mine) mother makes goods spaghetti sauce too. (Her/ Hers) is thick and rich.
B: In truth, making spaghetti sauce is easy, but everyone’s sauce is just a little different.
8.
a, - Trích mẫu thử.
- Nhỏ vài giọt từng mẫu thử vào quỳ tím.
+ Quỳ hóa đỏ: axit axetic
+ Quỳ không đổi màu: etyl axetat
- Dán nhãn.
b, - Trích mẫu thử.
- Nhỏ vài giọt từng mẫu thử vào giấy quỳ tím.
+ Quỳ hóa đỏ: axit axetic
+ Quỳ không đổi màu: rượu etylic
- Dán nhãn.
c, - Trích mẫu thử.
- Cho từng mẫu thử pư với Na.
+ Na tan, có hiện tượng sủi bọt khí: rượu etylic.
PT: \(Na+C_2H_5OH\rightarrow C_2H_5ONa+\dfrac{1}{2}H_2\)
+ Không hiện tượng: etyl axetat.
- Dán nhãn.
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9.
\(n_{CO_2}=\dfrac{8,8}{44}=0,2\left(mol\right)=n_C\)
\(n_{H_2O}=\dfrac{4,5}{18}=0,25\left(mol\right)\Rightarrow n_H=0,25.2=0,5\left(mol\right)\)
Gọi CTPT của A là CxHy.
⇒ x:y = 0,2:0,5 = 2:5
→ A có dạng (C2H5)n
\(\Rightarrow n=\dfrac{58}{12.2+5}=2\)
Vậy: A là C4H10.
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