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Chọn từ được th phát âm khácô đậm có các :
1/ A. so B.show C.who D.though
2/ A.waste B.wash C.wall D.walk
3/A.money B.love C.brother D.move
4/A.last B.taste C.fast D.task
5/A.coop B.door C.food D.boot
I. Choose the best answers.
1. I used to .................. money by delivering vegetables to the city.
A. earm B. get C. make D. A&C
2. It is wonderful ........................... the weekend in the countryside.
A. spend B. spending C. to spend D. spent
3. There is a meeting .......................... 9 a. m and 4 p. m on Sunday.
A. at B. between C. to D. on
4. Would you like ............................. now or shall we wait until the end?
A. go B. to go C. going D. went
5. When I entered the room, the baby ........................ quietly.
A. is sleeping B. was sleeping C. slept D. were sleeping
6. I hate .................... T.V, but like .............. books.
A. watch reading B. watching reading C, watching/readD. watch/read
7. You don't play computer games,........................... ?
A. do you B. don't you C. did you D. didn't you
8. He often does his homework ........................ the morning.
A. on B. at C. in D. for
9. Did he .................... live in the country when he was young?
A. use to B. used to C. get used to D. be used to
10. Bill wishes he ....................... more money so he could buy a new bike.
A. has B. have C. had D. having
III. Give the correct word formation.
1. Every week, there are two ..........flights............... from Ha Noi to Nha Trang. FLY
3. Graham hates queuing. He is very ................impatient............. .PATIENT
IV. Supply the correct tense of the words in brackets.
1. There (be) ............are............. 20 students in class 9A. They are learning English now .
2. When I (arrive) ...........arrived.......... yesterday, he was watching TV.
3. They (live) ..........have lived.......... here since 2003.
4. A modern hospital should (build) ................be built.......... in this town soon.
5. I (not hear).......haven't heard....... from my uncle for a long time.
V . Rewrite sentences, using "I wish ............... ''
1. I don't know many English words.
-> I wish I knew many English words.
2. My friend can not stay with me longer.
-> I wish my friend could stay with me longer.
3. The teacher said to them, Don't make noise in class.''
-> The teacher told them not to make noise in class.
4. They once started these machines by hand.
-> They used to start these machines by hand.
5. I asked Nga, ''Which book are you reading?''
-> I asked Nga which book she was reading.
6. ''Are you hungry? she asked me.
-> She asked me if I was hungry.
VI. Read the passage and choose TRUE or FALSE statements.
A boy was riding a bike when he had an accident He fell off his bike and his head on the road. His head was hurt it was bleeding. However, he was still conscious. It was an emergency so people called an ambulance, in order to take him to hospital. Some people tried to stop the bleeding by using a handkerchief to cover the wound Then they put pressure on it and held tight. After ten minutes, the ambulance arrived and people took the victim to hospital.
1/ The boy had a bike accident ........T.......
2/ His left hand was broken ........F.......
3/ The boy was still unconscious ........F........
4/ People covered his wound with a thick bandage ......F.....
5/ The boy was taken to hospital after ten minutes ........T.......
The lions are fed at 3 pm every day.
2. We got lost because we didn't have a map.
If we had had a map, we wouldn't have got lost.
3. I would prefer you to deliver the sofa on Friday.
I would rather you delivered the sofa on Friday.
4. The bridge was so low that the bus couldn't go under it.
It was such a low bridge that the bus couldn't go under it.
5. That was a silly thing to say.
What a silly thing to say!
6. We've run out of tea.
There isn't any tea left.
7. I last saw him when I was a student.
I haven't seen him since I was a student.
8. Susan was too excited to sleep.
Susan was so excited that she couldn't sleep.
9. Robert has not had a job for two years.
Robert has been unemployed for two years.
10. She will complete the work only she is paid extra.
She will not complete the work unless she is paid extra.
1. All the students love the principal. He is very kind. (because of)
All the students love the principal because of his kindness
2. I have forgotten the tickets. I’m sorry for it. (having)
I’m sorry for having forgotten the tickets.
3. I saw it with my own eyes. I believed it. (if)
If I hadn’t seen it with my own eyes, I wouldn’t have believed it.
4. The house at the end of the street has been sold. It has been empty for years. (which)
The house at the end of the street which has been empty for years has been sold.
5. It's a pity he doesn't take the doctor's advice. (wish)
I wish he took the doctor's advice.
1. The keepers feed the lions at 3 pm every day.
The lions are fed by the keepers at 3pm every day.
2. We got lost because we didn't have a map.
If we had had a map, we wouldn't have got lost.
3. I would prefer you to deliver the sofa on Friday.
I would rather you delivered the sofa on Friday.
4. The bridge was so low that the bus couldn't go under it.
It was such a low bridge that the bus couldn't go under it.
5. That was a silly thing to say.
What a silly thing to say!
6. We've run out of tea.
There is no tea left.
7. I last saw him when I was a student.
I haven't seen him since I was a student.
8. Susan was too excited to sleep.
Susan was so excited that she couldn't sleep.
9. Robert has not had a job for two years.
Robert has been unemployed for two years.
10. She will complete the work only she is paid extra.
She will not complete the work unless she is paid extra.
1. All the students love the principal. He is very kind. (because of)
-> Because of the principal's kindness, all the students love him.
2. I have forgotten the tickets. I’m sorry for it. (having)
-> I'm sorry for having forgotten the tickets.
3. I saw it with my own eyes. I believed it. (if)
-> If I hadn't seen it with my own eyes, I wouldn't have believed it.
4. The house at the end of the street has been sold. It has been empty for years. (which)
-> The house at the end of the street which has been empty for years has been sold.
5. It's a pity he doesn't take the doctor's advice. (wish)
-> I wish he took the doctor's advice.
1.lonlely
2. coldly
3. bad
4. làn sóng
5. máy may
6. tủ lạnh gấu trúc
=))) cũng không biết có đúng không nếu đúng tick cho mị nhé :"> love
28,75%
36
28,8%
Nồng độ phần trăm của dung dịch
FeCl3FeCl3bão hòa ở
20∘C20∘Clà khoảng
28 , 75 %.
- 𝑀𝐹𝑒𝐶𝑙3 =56 +35 , 5 ×3 =162 , 5 g/mol
- 𝑀𝐹𝑒𝐶𝑙3.6𝐻2𝑂 =162 , 5 +6 ×18 =270 , 5 g/mol
Bước 2: Tìm khối lượng FeCl3𝐹𝑒𝐶𝑙3 nguyên chất có trong 91 , 8 g tinh thểTrong 270 , 5 g tinh thể FeCl3.6H2O𝐹𝑒𝐶𝑙3.6𝐻2𝑂 có 162 , 5 g FeCl3𝐹𝑒𝐶𝑙3.
Vậy trong 91 , 8 g tinh thể FeCl3.6H2O𝐹𝑒𝐶𝑙3.6𝐻2𝑂 sẽ có khối lượng FeCl3𝐹𝑒𝐶𝑙3 là:
mFeCl3=91,8×162,5270,5≈55,148g𝑚𝐹𝑒𝐶𝑙3=91,8×162,5270,5≈55,148g Bước 3: Tính tổng khối lượng dung dịch bão hòa
Theo định nghĩa độ tan, dung dịch bão hòa được tạo thành từ 91 , 8 g tinh thể và 100 g nước:
mdd=mtinh th+mH2O=91,8+100=191,8g𝑚𝑑𝑑=𝑚tinhth+𝑚𝐻2𝑂=91,8+100=191,8g Bước 4: Tính nồng độ phần trăm ( 𝐶 %) của dung dịch FeCl3𝐹𝑒𝐶𝑙3
Nồng độ phần trăm được tính dựa trên khối lượng chất tan FeCl3𝐹𝑒𝐶𝑙3 nguyên chất (không tính phần nước kết tinh):
C%=(mFeCl3mdd)×100%=(55,148191,8)×100%≈28,75%𝐶%=𝑚𝐹𝑒𝐶𝑙3𝑚𝑑𝑑×100%=55,148191,8×100%≈28,75% Kết luận Nồng độ phần trăm của dung dịch FeCl3𝐹𝑒𝐶𝑙3 bão hòa ở 20∘C20∘𝐶 là khoảng 28 , 75 %
Độ tan: 91,8 g FeCl₃·6H₂O / 100 g H₂O M(FeCl₃) = 162,5 M(FeCl₃·6H₂O) = 270,5 👉 Khối lượng FeCl₃ trong 91,8 g muối: = 91,8 × (162,5 / 270,5) ≈ 55,2 g 👉 Tổng khối lượng dung dịch: = 100 + 91,8 = 191,8 g 👉 C% = (55,2 / 191,8) × 100 ≈ 28,8%
Ta có: 91,8 g FeCl₃·6H₂O chứa
m(FeCl₃) = 91,8 × \frac{162,5}{270,5} ≈ 55,2 g
⇒ Dung dịch bão hòa có: 55,2 g FeCl₃ + 100 g H₂O → 155,2 g dung dịch
⇒ C\% = \frac{55,2}{155,2} × 100\% ≈ 35,6\%
Đáp án: 35,6%