Mn2O7 --> HMnO4
MnO2 --> cái này là oxit lưỡng tính nha bạn
SO2 ---> H2SO3
NaCl không phải là oxit
Đáp án:
Giải thích các bước giải:
Mn ơi giúp e 2 câu lũy thừa, logarit này với ạ. E cảm ơn
I. Choose the word with the underlined part pronounced differently in each line: A. thin B. than C. they D. there A. birthday B. earth C. worth D. there A. another B. death C. brother D. though A. thank B. mother C. thunder D. throat A. they B. three C. thirst D. thread Answer: 1......, 2......, 3 ......, 4........., 5..........., II. Complete each sentence with a suitable question word: 1. _____ did you live last year? - In London. 2. _____ lessons do you have today? - Five. 3. _____ is that man at the door? - My uncle. 4. _____ do you go shopping? - At 4o’clock. 5. _____ do you feel? – Happy. 6. _____ is your sister? - 7 years old. 7. _____ does the concert start? - At 8p.m 8. _____ nationality are you? - American. III. Make questions for the underlined words or phrases. 1. He lives in a county house with his friends. 2. They are moving to an apartment next month. 3. She often plays badminton with her friends. 4. The pictures are on the wall. 5. There are two pillows on the bed. 6. The dog is in front of the computer. 7. There is a bookshelf next to the table. 8. Mi’s new house has two bedrooms IV. Complete the sentences with suitable conjunctions: 1. She likes swimming ..... jogging. 2. We were late .... there was an accident. 3. I like Paris .... I want to go home now. 4. I didn’t feel well .... I stayed at home. 5. I am very exciting ... I am meeting my favourite MC. 6. You can watch TV now ....... don’t spend too much time on it. tiếp theo I. Choose the word whose underlined part is pronounced differently from the others 1. A. arrived B. believed C. received D. hoped 2. A. opened B. knocked C. played D. occurred 3. A. rubbed B. tugged C. stopped D. filled 4. A. dimmed B. travelled C. passed D. stirred 5. A. tipped B. begged C. quarrelled D. carried 6. A. tried B. obeyed C. cleaned D. asked 7. A. packed B. added C. worked D. pronounced 8. A. watchedB.phoned C. referred D. followed II. Complete the sentences using the past simple form of the verbs. 1. I _____ at home last weekend. (stay) 2. Angela ______ to the cinema last night. (go) 3. My friends _______a great time in Nha Trang last year. (have) 4. My vacation in Hue ______ wonderful. (be) 5. Last summer I _____ Ngoc Son Temple in Ha Noi. (visit) 6. My parents ____ very tired after the trip. (be) 7. I _______ a lot of gifts for my little sister. (buy) 8. Lan and Mai _______ sharks, dolphins and turtles at Tri Nguyen aquarium. (see) 9. Trung _____ chicken and rice for dinner. (eat) 10. They ____ about their holiday in Hoi An. (talk) III. Write the negative from the positive sentences. 1. My friends and I went to the theatre two days ago. 2. He played his electric guitar in the past. 3.We ate in the restaurant yesterday. 4. My parents arrived at 7a.m to take me to the airport last week. 5. The doctors wore blue uniform last month. 6. We waited for my mum to take us to school yesterday. 7. They went to hospital in 2018. 8. She went to the supermarket and bought some food last week. 9. They opened a new library two months ago. 10. My friends watched a video clip on youtube three days ago. Write complete sentences. Use the past simple of the verbs. 1. you/ go swimming/ yesterday? 2. My father/ play golf/ yesterday 3. Phong/ listen to music/ two hours ago. 4. We/ not go/ school last week. 5. Lan/ cook/ chicken noodles/ dinner last night.
Cho dãy số : a1 = 1 a2 = 2 + 3 a3 = 4+5+6 a4 = 7+8+9+10 a) Tìm số hạng đầu tiên của a50 b. Tính a50
Nêu quy ước về chiều dòng điện? So sánh chiều quy ước của dòng điện với chiều dịch chuyển có hướng của các eelectron tự do trong dây dẫn kim loại?
Viết phần phân tích giải phương trình sau bằng phương pháp đặt ẩn phụ : $245x ^ 4 - 420x ^ 3 + 733 x ^ 2 - 474x + 304 = 0$
Cho PT: x ²+2x-m ²-1=0 Tìm m để PT có 2 nghiệm thỏa mãn x1=-3x2
giải hộ mình bài 2 và bài 3 vớii
Bài 1: Hai chiếc xe máy chuyển động đều trên cùng một đường thẳng. NẾU chúng đi lại gần nhau thì cứ 6 phút khoảng cách giữa chúng lại giảm đi 6km. Nếu chúng đi cùng chiều thì cứ 12 phút khoảng cách giữa chúng lại tặng lên 2km. TÍNH vận tốc mỗi xe? Bài 2: một hs đi từ nhà đến trường, sau khi đi đc 1/4 đoạn đg thì chợt nhớ mình quên một cuốn sách nên trở về lấy và đi tới trường thì trễ mất 15phút a. Tính vận tốc của hs biết đoạn đường từ nhà đến trường dài 6km, bỏ qua thời gian lên xuống xe. b.Để đúng thời gian như dự định thì quay về nhà lần 2, người học sinh phải đi vs vận tốc bao nhiêu? Các bạn giúp mình nhé!
Cho Tam giác Abc vuông tại A, AH vuông góc với BC tại H. Trên đường thẳng vuông góc Với BC tại B lấy điểm D( D và A ko cùng thuộc nửa mặt phẳng BC) sao cho BD=AH A) ch/minh tam giác AHB=tam giác DBH B) hai đường thẳng AB và DH có song song với nhau ko? Vì sao? C) tính <ACB,biết <BAH=35 độ Mình ko biết vẽ hình
Are cartoons always nice? The first time I took my daughter to the movie theater she was 6 and the movie was “Bambi”. I’m a movies lover, so I had chosen it carefully and thought a cartoon movie would be an effective introduction to the Seventh Art World. Everything was going just fine until Bambi’s mother was shot and killed. My daughter got anguished and asked to go home in the middle of the movie. Fortunately, later choices turned out OK and she likes movies as much as I do. My point is: are cartoons really safe for kids? Or do parents need to pay attention to the type of cartoons kids are watching during their spare time? Once I sat on the sofa to watch a cartoon with my 8-year-old son and got completely dumbfounded when I realized a cartoon character was agonizing right in front of us, bleeding as if it was an action adult movie! Everybody knows that the cartoon “The Simpsons” doesn’t spread nice manners or behavior, but what about the “kid stuff” they display in the afternoon for young children? The next time you take a kid to the movies maybe a cartoon doesn’t make the best choice, unless you take the time to watch it and analyze its content first. Or you take the risk of exposing your child to messages s/he isn’t prepared to get yet. 31. There isn’t violence in cartoon movies. T F 32. Parents shouldn’t worry about the cartoons content. T F 33. “The Simpsons” spreads nice manners and behavior. T F 34. Young children may feel anguished when they are exposed to things they are not prepared to deal with. T F 35. Before taking a child to the movies, it’s important to check the movie content. T F
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