1,Để nhận ra khí cacbondioxit,người ta thường dùng:

A.Nước vôi trong

B.Nước

C.Nước muối

D.Rượu etylic

2,Khí nitơ và khí oxi là 2 thành phần chính của không khí.Nito lỏng sôi ở -196 độ C,oxi lỏng sôi ở -183 độ C.Vì vậy:

A.Có thể tách riêng bằng phương pháp hóa lỏng không khí

B.Có thể tách riêng bằng phương pháp lọc

C.Không thể tách riêng 2 chất này

D.Có thể tách riêng bằng cách dùng phễu chiết

3,Một hợp chất có phân tử gồm 2 nguyên tử của nguyên tố Y liên kết với 1 nguyên tử O và nặng hơn phân tử hidro 47 lần.Y là nguyên tố nào sau đây:

A.Ca

B.Na

C.K

D.Li

4,Phân tử Axit sunfuric gồm 2H,1S và 4O.Phân tử này có khối lượng:

A.Nhẹ hơn phân tử Hidro

B.Nặng gấp 2 lần phân tử Oxi

C.Nhẹ hơn phân tử nước

D.Nặng gấp 3,0625 lần phân tử Oxi

M.n giải thích chi tiết rõ ràng giúp e với ạ,tại e không hiểu đề,e cảm ơn!

Exercise 8: Read the text and do the tasks that follow.

Houses for lease

#1 I have a beautiful double bedroom available in an apartment to share with one other person. The apartment is on the 12th floor and the room itself is a large double bedroom with two big beds under the window. There is a lamp and a chest of drawers between the two beds. In the corner of the room, there is also a wardrobe and a bookshelf. The apartment has a modern kitchen and an open living room. It is only a 5-minute walk to the bus stop. A one month deposit is needed, but there are no other fees.

#2 We have a large unfurnished double room, in a really nice house in the city. It's a big and clean house with a beautiful street view. The house is a 10-minute walk from the station. There is a shared living room, bathroom and kitchen with an air-conditioner, two ceiling fans, a microwave, a television and four armchairs. The minimum term is three months and the deposit is one month's rent.

#3 The room is in a two bedroom house that is very close to the bus stop going to the town. There is a kitchen next to the room and it's furnished including a dishwasher. There are also two large modern bathrooms with separate showers. The room is facing the garden and it is nice and quiet. It's good for people who enjoy a quiet but sociable life. The house is occupied by a mother and her 10-year-old son. Both are very nice and friendly. The rent is all inclusive - no more charges.

1. Match the following titles with the corresponding paragraphs.

1. A Nice Double Room To Rent Within A Modern Apartment

2. A Double Room To Rent In A Big House, Very Close To The Station

3. A Double Room In A Quiet Area Paragraph 3

Paragraph 2

Paragraph 1

2. Fill in the blank with number 1, 2, or 3 corresponding to the three houses mentioned in the passage.

1.____________ There are 2 beds in the bedroom.

2. ____________It is very near the bus stop to the town.

3. ____________You must rent it at least 3 months.

4. ____________You will live with another person if you rent this house/ apartment.

5. ____________There isn't any furniture in this room.

6. ____________The kitchen is next to the bedroom.

7. ____________There are two bedrooms in this house/ apartment.

8. ____________You will live with a woman and a boy in this house/ apartment.

9. ____________It takes you about five minutes to walk to the bus stop.

10. ____________You will share the bathroom and the kitchen with others in this house/ apartment.

3. Choose the best answer to complete the blank.

1. You have to pay one month in advance if you rent the house/ apartment ________.

A. 1 & 2 B. 2 & 3 C. 1 & 3

2. You can see the street if you rent the house/ apartment ________.

A. 1 B. 2 C. 3

3. The kitchen in the house/ apartment ________ is furnished.

A. 1 & 2 B. 2 & 3 1 & 3

Cho phương trình hóa học sau: C₃H₈ + O₂ ---------> CO₂ + H₂O

Bạn Phương cân bằng PTHH trên như sau: 2C₃H₈ + 10O₂ --------> 6CO₂ + 8H₂O

Hãy kiểm tra xem bạn Phương đã cân bằng phương trình đúng chưa? Nếu chưa đúng, hãy sửa lại.

Hòa tan hoàn toàn 1,2g MgO vào 300 ml dd H₂SO₄

a.      Tính nồng độ mol của axit đã dùng

b.      Tính khối lượng muối tạo thành.