-Thứ nhiệt: làm lạnh gói gel lạnh

- toả nhiệt: đốt củi trong bếp

a) Hiện tượng và phương trình hóa học Hiện tượng: Khi trộn dung dịch CaCl₂ và AgNO₃, sẽ có chất rắn AgCl màu trắng kết tủa. Phương trình phản ứng: CaCl 2 ( 𝑎 𝑞 ) + 2 AgNO 3 ( 𝑎 𝑞 ) → Ca(NO 3 ) 2 ( 𝑎 𝑞 ) + 2 AgCl ( 𝑠 ) CaCl 2 (aq)+2AgNO 3 (aq)→Ca(NO 3 ) 2 (aq)+2AgCl(s) b) Khối lượng AgCl sinh ra Tính số mol của CaCl₂ và AgNO₃: CaCl₂: 0,00378 mol AgNO₃: 0,01 mol Do tỷ lệ phản ứng là 1:2, nên CaCl₂ sẽ là chất giới hạn, và số mol AgCl tạo thành là 0,00756 mol. Khối lượng AgCl: 0,00756mol×143,32g/mol=1,083g c) Nồng độ AgNO₃ dư Sau phản ứng, AgNO₃ dư còn lại là 0,00244 mol. Thể tích dung dịch sau phản ứng là 0,1 L (100 ml). Nồng độ AgNO₃ dư: 0,00244 mol =0,0244M. Kết quả: Khối lượng AgCl: 1,083 g. Nồng độ AgNO₃ dư: 0,0244 M.

Khối lượng muối khan là :35,21g

1.trồng nhiều cây xanh

2.trồng các cây có khả năng lọc tốt

• The local festival is different from the international festival in its scale.
• The next semester will start on 5th January.
• Although the bus was late, I still arrived at school on time yesterday.

• Despite being tired, I stayed up late to complete my homework.
• Staying in a hotel is more comfortable than camping.
• My son used to read comic books every night when he was nine.
• You must not take photos in the museum.

1.Schools typically have breaks during the summer and tet holiday

2.People will use self -driving cars to travel around cities more esaily

3. You must show your passport at the airport security check.

1. Do you think studying abroad is good or bad? Why?
I think studying abroad is good because it helps students learn about new cultures, become more independent, and improve their language skills.

2. What do you think about public transportation in Vietnam?
Public transportation in Vietnam is improving, especially in big cities like Hanoi and Ho Chi Minh City. However, buses can still be crowded and not always on time.

3. Can you describe a traditional festival in your country?
Yes, Tet is the most important traditional festival in Vietnam. It marks the Lunar New Year. Families clean their homes, prepare special food, and visit relatives during this time.

4. Can you tell me about a time when you used English on vacation?
Last summer, I went to Da Nang and met some foreign tourists. I helped them find their hotel by giving directions in English.

5

1.My full name is Trieu Thi Ngan Hien

2.My favorite subject is English because I enjoy learning new words and expressing myself.

3.I use public transportation about three to four times a week

4.I like TET the most because of the decorations, visit grandparents, and time with family.

5.I use English outside school a few times a week, especially when watching movies or using the internet.

a)A: là biến cố ngẫu nhiên

B:Là biến cố chắc chắn

C:là biến cố không thể

b)