Đáp án:
Giải thích các bước giải:
$a/$
Gọi CTHH của A là $Y_2O_3$
Mặt khác :
$M_A = 2M_{SO_3}$$⇒ 2Y + 16.3 = 2.80$
$⇔ Y = 56$
Vậy Y là Sắt . Kí hiệu : $Fe$
$b/$
CTHH của A : $Fe_2O_3$
a,
A: $Y_2O_3$
$M_A=80.3=160$
$\Rightarrow 2Y+16.3=160$
$\Leftrightarrow Y=56(Fe)$
Vậy Y là sắt.
b,
A: $Fe_2O_3$
b1: Complete the sentences with " than , as , less or more " 1. bill's books are colorful than this friend's. 2. nobody is happier Maria Elena. 3. the boys felt worse the girls about losing the game. 4. they have money we do. 5. the Empire Stale Building is taller the statue of Liberty. 6. California is father from New York Pennsylvania. 7. Tom reads quikly than his sister. 8. no animal is so big King Kong. 9. I'm afraid that is report is impressive than the government's.
I last went shopping two months ago (gone) => I...................two months Our last holiday was in China (to) => We ..........our last holiday I've been here for two hours, and I'm still waiting (waiting) => I............two hours I haven't seen him for ages (since) => It's.............saw him The burglar escaped before the police arrived(had) => when the police............escaped Fred fell off the ladder while painting a wall (was) => while........, he fell off the ladder The workmen finished, and then Mr Jackson came home (when) => The workmen ........came home Alice made an appointment, and went to see the doctor (making) => Alice went to.....an appointment First he booked the restaurant, and then he invited everybody (before) => he booked the restaurant...........everybody
giúp em 2 bài này rồi em cho hay nhất nhé
I (work) here fora long time
bài 5 ý C em cảm ơn kết quả rút gọn là x-3 trên 6 ạ
Mn giúp mk đc ko??mk cần gấp lắm trc 5h
Vẽ bé này đi nhớ vẽ full có màu tô bằng màu nc Ko phòng cảnh cũng dc
1)giải cắc phương trình sau (x ²+x) ²+4(x ²+x)=12 2)cho tam giác ABC vuông cân tại A. Các điểm D,E theo thứ tự di chuyển trên AB,AC sao cho BD=AE.Xác điịnh vị trí điểm D,E sao cho: a)DE có độ dài nhỏ nhất b)tứ giác BDEC có diện tivhs nhỏ nhất
câu 6 thôi nhé mik cần gấpppppp
Exercise 6. Choose the correct sentence by joining the two simple sentences. Use the conjunction given. 1. I want to eat some food. I have a sore throat. (but) A. But I want to eat some food, I have a sore throat B. I want to eat some food, but I have a sore throat 2. The Japanese eat healthily. They live for a long time. (so) A. The Japanese eat healthily, so they live for a long time B. So they live for a long time, The Japanese eat healthily 3. I feel tired. I feel weak. (and) A. I feel tired, and I feel weak B. I feel and tired, feel weak 4. You can go and see the doctor. You can go to bed now and rest. (or) A. You can go or see the doctor, you can go to bed now and rest B. You can go and see the doctor, or you can go to bed now and rest Exercise 7. Choose the correct sentences. 1. A. I have stomach ache, so I don't want to eat anything B. I have stomach ache, or I don't want to eat anything 2. A. My mother eats a lot of fruit and vegetables, so she does exercise every morning B. My mother eats a lot of fruit and vegetables, and she does exercise every morning 3. A. My cousin Trang is very fat, but she is too lazy to walk B. My cousin Trang is very fat, or she is too lazy to walk 4. A. You can eat less, but you can do more exercise B. You can eat less, or you can do more exercise 5. A. I have flu, but I don't feel very tired B. I have flu, so I don't feel very tired 6. A. The Japanese eat a lot of fish, so they eat a lot of tofu, too B. The Japanese eat a lot of fish, and they eat a lot of tofu, too 7. A. The Americans often eat fast food, so many of them are overweight B. The Americans often eat fast food, but many of them are overweight 8. A. You can walk so you can ride a bike to get there B. You can walk or you can ride a bike to get there
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