Cho phản ứng hydrogen hóa ethylene sau:

H₂C=CH₂(g) + H₂(g) → H₃C-CH₃(g)

Biết năng lượng trung bình các liên kết trong các chất cho trong bảng sau:

Liên kết	Eb (kJ/mol)	Liên kết	Eb (kJ/mol)
C=C	612	C-C	346
C-H	418	H-H	436

 

Biến thiên enthalpy (kJ) của phản ứng có giá trị là

Sử dụng pháp luật được hiểu là công dân sử dụng đúng đắn các quyền của mình, và được làm những gì mà pháp luật:

Theo phân chia cấp THPT, ở lớp 10, các em sẽ được tìm hiểu lĩnh vực nào của sinh học?

Ý nào đúng: Nguyên tắc “linh kiện có sẵn trên thị trường” là nguyên tắc thứ mấy trong thiết kế mạch điện tử?

Read the following passage about studying abroad and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.

Successful students often do the followings while studying. First, they have an overview before reading. Next, they look for important information and pay greater attention to it (which often needs jumping forward or backward to process information). They also relate important points to one another. Also, they activate and use their prior knowledge. When they realize that their understanding is not good, they do not wait to change strategies. Last, they can monitor understanding and take action to correct or “fix up” mistakes in comprehension.

Conversely, students with low academic achievement often demonstrate ineffective study skills. [I] They tend to assume a passive role in learning and rely on others (e.g., teachers, parents) to monitor their studying. [II] For example, low-achieving students often do not monitor their understanding of content; they may not be aware of the purpose of studying; and they show little evidence of looking back or employing “fix-up” strategies to fix understanding problems. [III] Students who struggle with learning new information seem to be unaware that they must extend effort beyond simply reading the content to understand and remember it. [IV] 

Children with learning disabilities do not plan and judge the quality of their studying. Their studying may be disorganized. Students with learning problems face challenges with personal organization as well. They often have difficulty keeping track of materials and assignments, following directions, and completing work on time. Unlike good studiers who employ a variety of study skills in a flexible yet purposeful manner, low-achieving students use a restricted range of study skills. They cannot explain why good study strategies are important for learning; and they tend to use the same, often ineffective study approach for all learning tasks, ignoring task content, structure or difficulty.

Which of the following can be inferred from the passage?

Mark the letter A, B, C, or D on your answer sheet to indicate the correct arrangement of the sentences to make a meaningful paragraph/letter in each of the following questions.

a. Also, volunteering helps students connect with the community, making them aware of the needs around them.

b. Additionally, students develop such important skills as teamwork and communication ones while they volunteer.

c. Firstly, students who do voluntary work gain valuable real-world experience which can help in their future careers.

d. Finally, doing volunteer work can be a rewarding experience, as students feel good about helping others.

e. High school students benefit from doing voluntary work in many ways.

Tổ chức Du lịch Thế giới viết tắt là gì?

Trong GIMP, lệnh nào được sử dụng để tạo dãy khung hình cho ảnh động dựa trên hiệu ứng có sẵn?

An ninh phi truyền thống bao gồm những vấn đề nào sau đây?

Mark the letter A, B, C or D to indicate the sentence that is closest in meaning to each of the following questions.

He was successful in his career thanks to his parents’ support.

Cộng đồng châu Âu đổi tên thành Liên minh châu Âu vào năm nào sau đây?

Trên thị trường, doanh nghiệp Q nhận thấy giá của nguyên vật liệu đang có xu hướng gia tăng, nhưng hợp đồng đã kí với đối tác không thể thay đổi giá, nên doanh nghiệp đã quyết định cắt giảm một số chi phí về xử lý chất thải để giữ chi phí sản xuất sản phẩm không tăng, đảm bảo được mức lợi nhuận ban đầu. Trong trường hợp trên, doanh nghiệp Q đã làm gì để đảm bảo được mức lợi nhuận ban đầu?

Kim loại nào sau đây không được gọi là kim loại kiềm?

Read the following passage about home schooling in the UK and mark the letter A, B, C or D on your answer sheet to indicate the best answer to each of the following questions from 23 to 30.

Full-time education in the UK is compulsory from the age of five to sixteen, but this doesn’t have to be in a school. Around 50,000 children are educated at home. This is called ‘homeschooling’.

 Parents take their children out of school for different reasons, like illness and the need for special care, or because the distance to the nearest school may be too far. Some children are simply unhappy at school. Whatever the reason, they’re allowed to study at home, although inspectors regularly check how they are getting on.

 Hayley and Jenny haven’t been to school for two years but they haven’t neglected their studies. Their mother worked out strict timetables for them, with hourly lessons for each day. She’s responsible for teaching them Maths, English, History and French. Their father teaches them Science and Geography. They study all the other school subjects online. ‘We have lessons with Dad in the evenings and at weekends,’ explains Hayley.

 The family’s home is in a remote part of Wales. ‘The girls were fine at school but they spent so much time getting to school, they were too tired to learn, says their mother, Julia”. ‘We had a family conference and in the end we decided to try homeschooling. So far, it’s been a big success, but the girls know that if they want to go back to school at any time, we’ll let them. We follow the normal school program of lessons, and they will take all the normal school exams.’

 There are disadvantages too, of course. ‘Social isolation is something I worry about,’ says Julia. They both seem happy and well-adjusted, but they haven’t really got friends who live locally. But in the summer holidays they go away on trips to summer camps, where they have no trouble mixing with people and making friends.’

According to paragraph 2, which of the following is NOT MENTION as a reason for homeschooling?

Read the following passage about food addiction and mark the letter A, B, C, or D on your answer sheet to indicate the best answer to each of the following questions from 31 to 40.

Few people would disagree that one of the world's most popular dishes is pizza. Twenty-two-year-old Zack certainly wouldn't. He would eat a variety of pizza-based items, including homemade pizza, precooked microwave pizza, and even pizza leftovers from the night before. He was consuming 800kg of pizza a year. As a child, Zack had eaten a wide variety of food. But he became addicted to pizza when he started secondary school. American school meals have often been criticised for the large amount of fast food present on the menu, and pizza is the star dish. Zack even spent all his pocket money on slices of pizza.

Naturally, Zack's family worried about his high-calorie, low-vitamin diet. So did Zack. In an attempt to break his addiction, Zack agreed to appear on a TV programme called Freaky Eaters. Its aim was to encourage food addicts to beat their addictions with the help of a psychologist and nutritionist. It wasn't easy. He had to eat a fish dish, while his brother sat in front of him enjoying... a pizza! However, Zack met the challenge and has never eaten pizza again.

Seventeen-year-old Stacy Irvine's friends visit her and discover that she has been rewarded thousands of free toys from fast food restaurants as a regular customer. Stacy's mother often gave her two-year-old girl a portion of fried chicken in a McDonald's restaurant. [I] Since then, Stacy has refused to eat anything else except for pieces of fried chicken, and as a result, her diet has created serious health. She has been warned that if she doesn't change her diet, she will die. [II] Stacy once collapsed due to lack of vitamins and nutrients and needed to be hospitalised. [III] She insisted that Stacy adopt a healthier lifestyle. However, worryingly, Stacy's mother said that while Stacy was beginning to understand the seriousness of her situation, she couldn't eat anything else but chicken nuggets. [IV]

Twenty-year-old Hanna Little was keen on chips. The only thing that Hanna consumed for fifteen years was one plate of chips after another. Not surprisingly, a diet that contained few nutrients and an excess of fat and carbohydrates could only have negative consequences. And it did because not only did Hanna develop health problems, but she also had to leave her job after collapsing at work. At five, Hanna became addicted to chips and refused to eat fruits and vegetables despite her mother's efforts. Hanna says that she was terrified of tasting the flavour of different types of food and she would feel anxious just at the idea of doing it. Parties, picnics and barbecues with friends and family used to be a nightmare. Furthermore, Hanna was soon seen as 'odd' by her friends' parents.

It wasn't until the age of sixteen that Hanna realised she had Selective Eating Disorder (SED). Despite this new knowledge, no solution was found. It wasn't until she lost her job before she started eating normally. Hanna sought therapy from psychologist Felix Economakis, who used hypnosis, a treatment that none of the doctors that she had seen before had mentioned, to get her to eat fruit after one one-hour session, and since then she has been willing to eat anything.... including chips!

(Adapted from Friends Global)

The word it in paragraph 4 refers to _____.

Vì sao vào buổi trưa nắng gắt thì không nên tưới nước cho cây?

(1) Làm thay đổi nhiệt độ đột ngột theo hướng bất lợi cho cây

(2) Giọt nước đọng trên lá trở thành thấu kính gây phản xạ ánh sáng làm lá không hấp thụ được ánh sáng cung cấp cho quang hợp

(3) Giọt nước đọng trên lá trở thành thấu kính hội tụ hấp thụ ánh sáng làm nóng lá hơn

(4) Đất nóng, tưới nước sẽ bốc hơi nóng, làm héo lá

Read of the following leaflet and mark the letter A, B, C or D on your answer sheet to indicate the option that best fits each of the numbered blanks from 7 to 12.

The True Cost of Convenience: Facts That Will Change Your Habits

When one plastic bottle is thrown away, (7)_________ will soon replace it in our landfills. Fast fashion companies (8)_________ millions of unsold clothing items each year.

The (9)_________ caused by single-use items affects our oceans and wildlife. (10)_________ their convenience, plastic straws harm marine animals.

The waste from our daily (11)_________ can take hundreds of years to decompose. A (12)_________ of people don't realize the impact of their daily choices on the environment.

Make small changes today for a better tomorrow! Choose reusable bags, bottles, and containers. Together, we can make a difference!

Ví dụ nào sau đây không phải đặc điểm thích nghi ở sinh vật?

Nếu từ các độ cao khác nhau ném ngang các vật với cùng vận tốc thì vật nào ném ở độ cao lớn hơn sẽ có tầm xa

Kí hiệu nào sau đây viết đúng mệnh đề: “\(\sqrt 5 \) không là số nguyên”?

Phương án nào sau đây không thuộc một trong các loại thuế của nước ta?