a) Nguyên tố X là nguyên tố Ca (canxi). Tự vẽ
b) Có 20 electron, 4 electron lớp ngoài cùng. X thuộc chu kì 4, nhóm ɪɪA
Đúng 0
Bình luận (0)
Các câu hỏi tương tự
1.I (be)......(am/was/were/is) happy after the summer vacation in Nha Trang.
2 her father wrote sick.....( Note/paper/ record/ check) because she was ill.
SD
4 tháng 7 2021 lúc 18:23
Khi axit sunfuric kết hợp với amoniac có tạo ra phản ứng gì hay không?
I). Change thế sentences into pasive. 1. Peter is writing a letter to his friend 2. My friends making some phone calls in the evening. 3. B ad drivers are causing many accidents 4. The children are eating a lot of sweets 5. Nam is repairing mt piano at the moment 6. They are demolishing the entire block 7. Someone is cutting the glass now 8 The factory is producing more and more pollution9 Someone is showing her now to do it10 The boys are plantting some trees in the garden11 L...
Đọc tiếp
I). Change thế sentences into pasive.
1. Peter is writing a letter to his friend
2. My friends making some phone calls in the evening.
3. B ad drivers are causing many accidents
4. The children are eating a lot of sweets
5. Nam is repairing mt piano at the moment
6. They are demolishing the entire block
7. Someone is cutting the glass now
8 The factory is producing more and more pollution
9 Someone is showing her now to do it
10 The boys are plantting some trees in the garden
11 Lan was prepairing that report when i came to see him
12. waiters and waitresses were serving customers
13. The president was signgs those papers
14. Was mary helping her mother in the kitchen at the time?
15. The head teacher was making the announcement
16 Someone was cleaning the windows while I was there
17 They sere preseting the athletes to the spectators when we came
18 Someone is making the coffee when I walk into the kitchen
19 They have sold their car to pay debts
20 No one has opened the windows for ages
21 No one has over asked me that question before
22 They haven't done anything since he left
23 A doctor has just examined Jonh
24 They haven't used this machine for ages
25 Peter has sung this song
26 They have paid doctor a lot of money
SD
13 tháng 6 2021 lúc 16:48
sunfuric là gì?công thức phân tử là gì?Ethane là gì?Công thức phân tử là gì?Cả hai có độc không?trả lời cụ thể
NN
3 tháng 8 2021 lúc 15:58
Viết các câu sau ở thể khẳng định , phủ định , nghi vấn của thì hiện tại đơn
1)
(+) He goes to the cinema every Sunday
(-)
(?)
2)
(+)
(-) James doesn"t like strawberry
(?)
3)
(+)
(-)
(?) Do they work in this sofeware company ?
4)
(+) His new trousers are back
(-)
(?)
Giúp mk với
Exercise 1: Fill in the blanks with SO, TOO, EITHER or NEITHER and auxiliary verb.1.Jim goes to school every day, _________Mary/ Mary ______2. Carol studied Biology, _________Paul/ Paul ________ 3.Mai is a very good student, ______Phuong/ Phuong_______4. Lily cant play the guitar, _________Rosie/ Rosie _________ 5. Mariana bakes delicious cakes, ________Cindy/ Cindy _________6. Ngoc Anh will sing tomorrow _______Mai/ Mai ___________ 7. Jonathan did the homework, _______Michael/ Michael _________...
Đọc tiếp
Exercise 1: Fill in the blanks with SO, TOO, EITHER or NEITHER and auxiliary verb.
1.Jim goes to school every day, _________Mary/ Mary ______
2. Carol studied Biology, _________Paul/ Paul ________
3.Mai is a very good student, ______Phuong/ Phuong_______
4. Lily can't play the guitar, _________Rosie/ Rosie _________
5. Mariana bakes delicious cakes, ________Cindy/ Cindy _________
6. Ngoc Anh will sing tomorrow _______Mai/ Mai ___________
7. Jonathan did the homework, _______Michael/ Michael __________
8. Erick has told a funny joke, ______ Sarah/ Sarah _________
9. They didn't eat the salad, ______I/ I _________
10. My mother hasn't finished the juice, _______my sister/ My sister __________
Exercise 3: Complete the sentences by using TOO and EITHER.
1. We often go swimming in the summer and they____________
2. John can ride a horse. I_________
3. Nam didn't come to the party last night and Minh___________
4. I will buy some oranges and pineapples. He___________
5. They don't want to go out tonight and we___________
6. The pineapples aren't ripe, and the bananas___________
7. Nam is hungry and his friends___________
8. Jane won’t come. Peter___________
9. Hoa had a medical check-up yesterday morning. We___________
10. He can't swim and his brother___________
Giúp hộ nha
2. This is the _________book I have ever read.
A. bad B. worse C. worst D. badly
3. Would you like me to get you something to drink? ~ _________.
A. That would be nice B. No, I’m sorry C. That’s too bad D. My pleasure