a) Fe + H2SO4 → FeSO4 + H2
b) n Fe = n H2 = 4,48/22,4 = 0,2(mol)
m Fe = 0,2.56 = 11,2(gam)
c) n H2SO4 = n H2 = 0,2(mol)
=> CM H2SO4 = 0,2/0,2 = 1M
ae lam ho mik cai nay
MN oi giuwps mik vs :((
Phân loại và gọi tên các chất sau :
Fes , Zno , SO3 , H3Po4 , Fe2O3 , Zn( HCo3 )2 , BaCl2 , N2O5 , HBr
ae vào làm hộ mik cái
Mọi Người Lam Giúp Mình Với ạ
lam hộ em câu 1 tự luận ạ
giả hộ câu 3 cái ae
Ae giúp tui mấy câu hóa cái :DD
lam the nao de tach hon hop gôm vun sat, vun nhom va mat go. biet khoi luong rien Dfe=7,8g/cm3,Dal=2.7g/cm3; Dgo= 0,8g/cm3
cac ban oi lam ho mik ban nay vs
I. Chia động từ trong ngoặc cho đúng thì (Give correct tenses of the verbs)
1. Mary (be) ____________________ seriously ill since last night.
2. They sometimes (go) ____________________ school by bus.
3. How long __________ you (study) __________ English?
- I (study) ____________________ it for 7 years.
4. We last (see) _____________ them last Sunday.
5. I (not meet) ____________________ him since he moved to Hanoi.
6. Now they (play) ____________________ happily in the school yard.
7. We (not finish) ____________________ our exercises yet.
8. My friend said he (be) __________ working in Hanoi then.
9. Mr. David (just buy) ____________________ a new house.
10. They (build) ____________________ a new hospital in my neighborhood next month.
11. It (not rain) ____________________ since the beginning of this month.
12. Lan asked me if I (like) __________ pop music.
13. We (begin) ____________ to learn English three years ago. Now we (learn) __________________ for 3 years.
14. __________ you ever (be) __________ to Ho Chi Minh City?
15. The telephone (ring) __________ when we (watch) ___________ television last night.
16. Mrs Hoa (teach) _________ English in this school since she (leave) ______ the university.
17. Look! That car (run) _________________ very fast.
18. The Browns (have) ____________________ dinner at the moment.
19. He (live) ____________________ in Hanoi for 20 years.
20. Alexander Graham Bell (invent) _____________ the telephone many years ago.
21. She (be) __________ very ill now. She (not go) ____________ to school since Monday.
22. + __________ you (be) __________ to Phong Nha before?
+ Yes. I (spend) _____________ my holiday there last summer.
23. I must go now. I (phone) ________ you when I (arrive) ______________ there.
24. When I last (see) __________ them, they ( work) ___________ in a factory in Hanoi.
25. Ba's teacher (give) __________ him a lot of homework last week.
26. Tom hopes he (meet) __________ many interesting people when he goes to Hanoi next month.
27. Mai and her friends (walk) ____________________ to school now.
28. They (go) __________ to Sao Mai Movie Theater last night.
29. She (not see) ____________________ that film before.
30. My mother was waiting for me when I (come) ______________ home.
31. Ann and Susan (cook) _____________________ dinner when Martin arrived home.
32. The light (go) ______________ out while we were having dinner.
33. + What __________ you (do) ______________ at this time yesterday?
+ I (play) _____________________ games on the computer.
34. Tom! Turn off the TV. You (always watch) ____________________ TV.
35. Lan often (do) __________ her homework carefully.
36. This is the first time Hoa (meet) ____________________ Tim's family.
37. They said they (go) ____________________ to Hanoi the following day.
38. Yesterday (be) __________ a beautiful day. The Sun (shine) ____________________ brightly when we (leave) ______________ home.
39. The teacher asked me if I (know) __________ where the Statue of Liberty was.
40. Listen! Mai (play) ____________________ the piano in her room.
41. + What kind of music ____________ you (like) __________ ?
+ I like pop music.
42. In summer, the Sun usually (shine) __________________ brightly.
43. I (not finish) _______________________ reading the novel you lent me yet.
44. Julia (write) ________________________ an email to her boy friend now.
45. Jack (not meet) _______________________ Tom the last time he came to America.
ae oi lam ho mik :)
