user-avatar
ngoccamtonnu65
2 năm trước
Tổng số hạt trong nguyên tử X là 40 và có số khối nhỏ hơn 28. a. Hãy viết các loại công thức của các loại phân tử litri clorua khác nhau biết litri có hai đồng vị: 7Li, 6Li. Clo có 2 đồng vị : 35Cl, 37Cl b. Có bao nhiêu phân tử khí cacbonic tạo thành từ 3 đồng vị oxi: 16O,17O,18O và 3 đồng vị hidro:1H,2H,3H c. Có bao nhiêu phân tử nước tạo thành từ 3 đồng vị oxi: 16O,17O,18O và 3 đồng vị hidro: 1H,3H,2H Giúp mình với ạ, mình đang cần ngay bây giờ😭
Thích Trả lời Chia sẻ

Các câu hỏi liên quan

I. Choose the word that has the underline, is pronounced differently from the rest (1pt) 1- A. recycle B- sky C- why D- century 2- A. resources B- beaches C- lakes D- oranges 3- A. meal B- ahead C- reading D- please 4- A. youth B- thank C- thirsty D- there 5. A- favor B- glad C- bank D- happy II/ Choose the best answer. (3 pts) 1. It is very.....to learn English. A- interest B- interested C- interesting D. interests 2. ....is very important because it help you practice the words. A- revision B- revise C- revising D. review 3. There are.....ways of learning new words. A- differ B- different C- differently D. differly 4. Our teacher asked us ________ in class. A. not to talk B. to not talk C. no talk D. without talking 5. We take part ________ most youth activities of our school. A. of B. on C. in D. at 6. You should ________ your lesson before the examination. A. read B. look C. revise D. study 7. His father is very proud ________ him. A. of B. with C. on D. about 8. Yesterday I came ________ your brother when I was going to school. A. of B. to C. about D. across 9. Last night he went home ________ 10 o’clock. A. until B. at C. After D. in front of 10. Lan enjoys ________ the piano. A. play B. playing C. plays D. played III/ Read the following passage then choose the correct answer by circling A, B, C or D.(2pts) The Y & Y is planning to help the community by encouraging all members to participate in a recycling program. All we have to do is to collect used glass, paper and cans, and send them for recycling. By doing this, we can help saving natural resources and earn some money for the organization. If possible, we can participate in other programs such as raising funds for the poor, helping street children and planting trees, flowers along the sidewalk or in the parks. If we do well all the plans as shown, we will make our life become more beautiful and lively. 1/. How is the Y & Y planning to help the community? …………………………………………………………………………………… 2/. After collecting cans, what do the Y & Y members do with them? ……………………………………………………………………….................... 3/. Can we help saving natural resources by taking part in these programs? …………………………………………………………………………………… 4/. What other programs can each member participate in? ………………………………………………………………………………………… VI/. Choose the underlined part that needs correcting (2pts): 1. He likes gardeningbut he hates dothe housework. A B C D 2. Her mother asked her not eat fruits before washingthem. A B C D 3. Did you used to go fishing with your uncle when you were young? A B C D 4. Tim should spend more timeinSpanish pronunciation. A B C D V/ Turn these sentences in to reported speech. (2 points) 1. “You should keep your room tidy” my mother told me. My mother told…………………………………………. 2. “Can you buy me some stamps?” Tom said to me. Tom asked……………………………………………… 3. “Don’t read the answer keys before you finish the task”, the teacher told us. The teacher advised……………………………………………………… 4. Those boys are interested in playing badminton. Those boys enjoy …………………………………………..

2018 © Loga - Không Ngừng Sáng Tạo - Bùng Cháy Đam Mê
Loga Team