Đáp án + giải thích các bước giải:
- Đồng phân `C_4H_9OH`
\begin{array}{|c|c|c|}\hline \text{STT}&\text{CTCT}&\text{Gọi tên}\\\hline \text{1}&\text{}CH_3CH_2CH_2CH_2OH&\text{butan-1-ol}\\\hline \text{2}&\text{}CH_3CH_2CH(OH)CH_3&\text{butan-2-ol}\\\hline \text{3}&\text{}CH_3CH(CH_3)CH_2OH&\text{2-metylpropan-1-ol}\\\hline \text{4}&\text{}CH_3C(CH_3)_2OH&\text{2-metylpropan-2-ol}\\\hline\end{array}
1) $CH_3-CH_2-CH_2-CH_2OH$
Tên gọi: butan-1-ol
2) $CH_3-CH(OH)-CH_2-CH_3$
Tên gọi: butan-2-ol
3) $CH_3-CH(CH_3)-CH_2OH$
Tên gọi: 2-metylpropan-1-ol
4) $CH_3-CH(OH)(CH_3)-CH_3$
Tên gọi: 2-metylpropan-2-ol
1. A: What (you /do) ________________? B: I (write) ________________a letter to my parents. I (write) ________________them very often. 2. A: Let’s go out. B: Look! It (snow) ________________outside. It (come) ________________down quite hard. 3. A: What time (you/ usually / start) ________________work? B: Normally we (start) ________________work at eight o’clock, but we (start) ________________at seven this week. We’re busy at the moment. 4. A: (you/ listen) ________________to the radio? B: No, you can turn it off. 5. A: I think we are going the wrong way. B: I don’t think so. The sun (rise) ________________in the east, remember. It’s behind us so we (travel) ________________west. 6. A: (you/look) ________________for someone? B: Yes, I (need) ________________to speak to Neil. Is he in? A: Yes, but I (think) ________________he’s busy. He (talk) ________________to the boss at the moment. 7. A: I (want) ________________a new computer. I (save) ________________up to buy one. B: But computers (cost) ________________so much money. What’s wrong with the one we’ve got? A: It (get) ________________out of date now. 8. A: Your new dress (look) ________________very nice. B: Thank you. The trouble is it (not/fit) __________ properly. I (not/know) ________________why I bought them, really. 9. A: What (you/do) ________________? B: I (weigh) ________________this letter. I (need) ________________to know how many stamps to put on it. 10. A: I (think) ________________this road is really dangerous. Look how fast that lorry (go) ________________. B: I (agree) ________________. People shouldn’t go so fast
C1: Trung thực có đồng nghĩa với khô khan, cứng nhắc, nói tất cả mọi điều ở mọi nơi, mọi lúc không? Vì sao? C2: Có khi nào nói dối là trung thực không, cho ví dụ, em rút ra bài học gì?
Phân tích các nguyên tắc của nguyên lý mối liên hệ phổ biến (cho ví dụ cụ thể)
Hãy tưởng tượng bn đang thăm bạn bè ở 1 vùng khác của Việt Nam . Hãy viết thư cho gia đình bạn Giúp em nhanh vs ạ
Bài 2. Một xe chuyển động thẳng không đổi chiều, trong nửa thời gian đầu xe chạy với vận tốc 24km/h. Trong nửa thời gian sau xe chạy với vận tốc 36km/h. Tính tốc độ trung bình trong suốt thời gian đi
I. Make sentences, using the words and phrases below 1.Tuan / find/ play / table-tennis / interesting / because / he / play / best friend. → 2.Why not / you / take / jogging? It / help / you / keep fit. → 3.When / you / start / hobby? → 4.I / enjoy / mountain / climbing / and / I / in / mountain climbing / club → 5.What / you / think / make / models? → 6.How / you / find / dance/ ?→ 7.You / take / collect / dolls / future? → 8.I / just / keep / bottles / after / use/ → 9.What / your / favourite hobby? → 10.You / share / this hobby / anyone / ? → hơi giài mong mn giúp mình nha :)
11. They ______________ (play) football and basketball at school. 12. My father ______________ (read) the newspaper every morning. 13. We ______________ (have) English, Maths and Science on Monday. 14. She never ______________ (do) her homework. 15. I ______________ (go) swimming twice a week. 16. Cars ______________ (be) more expensive than motorbikes. 17. Jane always ______________ (have) breakfast at 6 o’clock. 18 He usually ______________ (watch) TV after dinner. 19. London ______________ (be) a very big country. 20. I _____________ (be) a student and my parents ___________ (be) teachers. Ex 5. Put the adverb of frequency into the correct place. Then give the correct form of verbs. 1. My brothers (sleep) on the floor. (often) ____________________________________________________________________ . 2. He (stay) up late? (sometimes) ____________________________________________________________________. 3. I (do) the housework with my brother. (always) ____________________________________________________________________. 4. Peter and Mary (come) to class on time. (never) ____________________________________________________________________. 5. Why Johnson (get) good marks? (always) ____________________________________________________________________. 6. You (go) shopping? (usually) ____________________________________________________________________. 7. She (cry). (seldom) ____________________________________________________________________. 8. My father (have) popcorn. (never) ____________________________________________________________________. Ex 3. Change these sentences into negative (phủ định) and interrogative form (câu hỏi) 1. They listen to English every day. ____________________________________________________________________. 2. She plays badminton every afternoon. ____________________________________________________________________. 3. We play volleyball every morning. ____________________________________________________________________. 4. He does homework every night. ____________________________________________________________________. 5. Mary and Peter go to work every day ____________________________________________________________________. 6. He gets up at 9.00 every morning. ____________________________________________________________________
Bài 1. Một vật chuyển động thẳng không đổi chiều. Trên đường nửa nãng AB, vật đi nửa quãng đường đầu với vận tốc v1 = 40m/s, nửa quãng đường sau vật đi với vận tốc v2 = 30m/s. Tính tốc độ trung bình trên cả quãng đường
Vẽ mầm hoang mang NL: dưới bình luận
Giúp mik với làm phần làm văn thôi nha Ko mạng Cảm ơn
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