1 viên chloramin B 0,25 gam dùng để khử khuẩn 25 lít nước. Tính nồng độ mol của chloramin B có trong 25 lít nước

A. 4,68.10^-5M

B. 4,86.10^-5M

C. 8,68.10^-5M

D. 8,86.10^-5M

Khi sản xuất nước ngọt có gas người ta thường nen khí carbon dioxide ở áp suất cao nhằm mục đích gì?

A. Tăng khả năng hòa tan của khí carbon dioxide trong nước

B. Giảm khả năng hòa tan của khí carbon dioxide trong nước

C. Không làm thay đổi khả năng hòa tan của khí carbon dioxide trong nước

D. Giảm nhanh lượng khí carbon dioxide trong nước

Đánh dấu vào câu có cách sử dụng đúng số lượng. Nếu câu nào sai, hãy gạch chân lỗi sai đó và sửa lại.

1. The town doesn't have enough facilities for sports and shopping
2. It can be boring here because we do not have many entertainment
3. The village doesn't have pollution because there are not much vehicles
4. There are beautiful waterfalls and lots of wild birds here
5. The air is fresh in my moutain village because there are not much traffic jams

1. The/ ago/ ten/ started/ minutes/ film /.

→ ___________________________________________

2. watch/ you/ Did/ movie/ wild/ about/ the/ night/ animals/ last/ ?

→ _____________________________________

3. is/ an/ movie/ on/ There/ action/ theater/ Saturday/ on/ at/ night/ movie/ the/.

→ _____________________________________

4. is/ Mary/ red T-shirt/ wearing/ a/ black shorts/ and/.

→ _____________________________________                      

1. I think Chinese is more difficult than English.

      → I think English …………………………………………………

2. The other people in the team are much younger than Alice.

     → Alice is….……………………………………..………

3. It’s necessary for you to bring bottled water.

     → You……………………..…………………………………

4. The library is to the left of the supermarket and the bus station is to the right of the supermarket.

      → The supermarket…………………………………………..…………………

5. It’s not good for you to go hiking today.

     → You ….…………………………………….....

6. We took the bus to the campsite.

     → We went ………………………..……………………………………

7. I want to have a cheeseburger.

      → I would ……………………………………………………

8. Why don’t we go to the movie theater?

     → Let’s ….………………………………………...

9. Simon likes playing soccer in his free time.

     → Simon’s hobby………………………………………………

10. There are three bedrooms in my house.

      → My house ……………………………………………………………

11. I like literature and geography.

     → Literature and geography ….…………………………………………

12. Mrs. Smith has a daughter, Anna.

     → Mrs. Smith is ………………………..………

1. Mount Everest is _________ (high) mountain in the world.

2. It is _________ (noisy) in big cities than in small towns.

3. I think playing sports is _______ (good) than watching TV.

4. Who’s _________ (intelligent) student in your class?

5.Minh is the___________________student in our class.                                   (GOOD)

6.July is __________________than August.                                                        (HOT)

7.These bags are _____________________than those ones.                               (EXPENSIVE)

8.Living in the city is______________________than living in the countryside.      (NOISY)

9.Who is the____________teacher in your school?                                    (YOUNG

Chuyển sang câu bị động

1- People wash the used plastic bottles with water.

2- They always listen to music in the morning.

3- The students often play sports everyday.

4- I never drink coffee for dinner.

5- People reuse used paper to make shopping bags.

6- People also use the recycled plastic to make toys.

7- They use milk for making butter and cheese.

8- The man brings bottles of milk to my house.

9- People speak English all over the world.

10- They don’t use this house very often.

11- Do they teach French in this school?

12- They make a lot of beautiful toys from recycled plastic.

Write the comparative form of the adjective or adverb in brackets. Use "than" where necessary.

1. A cellphone would be a __________ present. (useful)

2. It's a long way from here to the station __________ I thought. (far)

3. Can't you think of anything __________ to say? (intelligent)

4. It was __________ usual in town today. (busy)

5. Unfortunately her illness was __________ we thought at first. (serious)

6. Health and happiness are __________ money. (important)

7. You need to draw it __________. (carefully)

8. I like living in the country. It's __________ living in the town. (peaceful)

9. We can't hear. Could you speak a little __________? (slowly)

10. I can't stay __________ half an hour. (long)