Trong mỗi ý a), b), c), d) ở mỗi câu, thí sinh chọn đúng hoặc sai.
Để điều chế một lượng nhỏ khí chlorine trong phòng thí nghiệm, người ta cho dung dịch HCl đặc phản ứng với MnO2 rắn theo sơ đồ thí nghiệm như hình dưới đây, trong đó bình (1) chứa NaCl(aq) giúp giữ khí HCl, bình (2) chứa H2SO4 (l) đặc giúp hút ẩm, làm khô khí, bảo đảm chất lượng chlorine.
Trong mỗi ý a), b), c), d) ở mỗi câu, thí sinh chọn đúng hoặc sai.
Để điều chế một lượng nhỏ khí chlorine trong phòng thí nghiệm, người ta cho dung dịch HCl đặc phản ứng với MnO2 rắn theo sơ đồ thí nghiệm như hình dưới đây, trong đó bình (1) chứa NaCl(aq) giúp giữ khí HCl, bình (2) chứa H2SO4 (l) đặc giúp hút ẩm, làm khô khí, bảo đảm chất lượng chlorine.
a. Dung dịch HCl đặc đóng vai trò là chất oxi hoá trong phản ứng điều chế chlorine.
b. Bông tẩm dung dịch NaOH giúp ngăn khí chlorine rò rỉ ra ngoài.
c. Khi thay MnO2 bằng KMnO4 cùng khối lượng, lượng Cl2 thu được sẽ nhiều hơn, biết HCl đặc dùng dư. Cho phương trình hoá học của phản ứng giữa KMnO4 và HCl là:
\(2{\rm{KMn}}{{\rm{O}}_4} + 16{\rm{HCl}} \to 2{\rm{KCl}} + 2{\rm{MnC}}{{\rm{l}}_2} + 8{{\rm{H}}_2}{\rm{O}} + 5{\rm{C}}{{\rm{l}}_2}\)
d. Nếu hoán đổi vị trí bình (1) và bình (2), chất lượng khí chlorine thu được sẽ không đổi.
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Triển vọng của ngành chăn nuôi là
Cho hàm số \(y=f(x)\) là một hàm đa thức có bảng xét dấu \(f^{\prime}(x)\) như sau:
Số điểm cực trị của hàm số \(g(x)=f\left(-2 x^2+|x|\right)\).
Mark the letter A, B, C, or D on your answer sheet to indicate the correct answer to each of the following questions.
Who will pay for the coach if almost two fifths of the passengers________ a free ride?
Read the following passage about fashion and mark the letter A, B, C, or D to indicate the best answer to each of the following questions from 31 to 40.
Fashion in the 1960s reflected the cultural and political upheaval of the time. The hippie and counterculture movement gave rise to accessories like Pocahontas-style headbands and medallions worn around the neck. Hippies wore long, loosely fitting clothing, often in natural fabrics. Hemlines rose as Mary Quant popularized the miniskirt and hot pants in her lines for JC Penney. And mod fashion, with brightly colored space-age geometric patterns, shift dresses and colored tights became the mainstream. Both miniskirts and mod-shift dresses were worn with knee-high go-go boots.
[I] During the 1970s, the loose-fitting hippie clothes of the prior decade gave way to exotic fabrics and bell-bottom jeans for men and women. Hemlines continued to rise and hot pants continued their popularity, reflecting the flashy style of the decade. However, the 1970s also saw the popularity of a longer hemline, from mid-calf to ankle-length. [II] Women wore peasant-style clothing, especially blouses with off-the-shoulder necklines and lace trim, with their jeans or skirts. [III] Disco fashion emerged, featuring bright patterns and tightly fitting clothing meant to show off the body. Platform shoes elevated their wearer, male or female, anywhere from two to four inches or more. [IV]
The 1980s saw another fashion upheaval. Angst-ridden punks wore Dr. Marten and steel-toed army boots, chains, tartan patterns, and bondage pants. Punks focused more on their hair during this period, dying, teasing and chopping their hair into asymmetric styles that seemed to defy gravity. Women–and men–experimented with heavy eyeliner in a variety of colors. Women wore neon colors, jelly shoes, tight jeans, leggings, leg warmers and oversized sweatshirts. Menswear-inspired looks also became popular for both sexes. Men wore ‘power suits,’ named so for their price, which made these suits a reflection of the wealth of the wearer. Women’s jackets featured big shoulder pads that made the shoulders appear higher and larger, similar to the male silhouette.
1990’s fashion was far more subdued than the garish, wild styles of the 1980s. Bands like Nirvana influenced the grunge look, which featured rock-concert tee shirts under plaid flannel shirts, jeans and long, greasy hair. Overalls were worn by both sexes, either with one or both shoulder straps unhooked. The punk style of the 1870s and 1980s evolved into the goth fashion trend, which featured black clothing, black boots and studded bracelets in the style of bands like Nine Inch Nails and Marilyn Manson.
Which of the following best expresses the essential information in the underlined sentence in paragraph 3?
Một vật dao động điều hòa dọc theo trục Ox với biên độ 20mm, tần số 2Hz. Tại thời điểm \(t = 0s\) vật đi qua vị trí có li độ 1cm theo chiều âm. Phương trình dao động của vật là:
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)
Which of the following best paraphrases the underlined sentence in paragraph 4?
Ý nào sau đây là thể hiện nội dung khái niệm của mô hình sản suất kinh doanh doanh nghiệp?
Cho tập hợp X = {x ∈ ℤ | (x2 – 3)(4x2 – 10x + 6) = 0}.
Tập hợp X có bao nhiêu phần tử?
Chọn ý đúng: Chọn lọc hỗn hợp áp dụng với loại cây nào?
Healthy mind, healthy body
“A healthy mind lives in a healthy body” is a saying (1) ______ to have often been used by the ancient Greeks. Thousands of years later, the same idea still applies. According to health experts, it’s advisable (2) ______ eight to ten glasses of water every day. However, water itself is not enough; a balanced diet is essential, too. A healthy body naturally is the result of doing exercise. Many people, however, do not like gyms and object to going there for different reasons. Some, for instance, say that aerobic sessions are too difficult to follow while others say that gyms are just too expensive. Many people also say that they have (3) ______ in finding time to exercise due to their busy lifestyle, but the truth is that everyone can make a little time every now and then. Regardless of the way people choose to exercise, it is important to remember that there’s no point (4) ______ doing it only for a short period of time. Last but not least, (5) ______ a positive attitude and doing away with negative thoughts contribute to one’s good health. In short, following (6) ______ surely helps in having a healthy mind and body.
Read the following advertisement 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 1 to 6.
Biện pháp nào sau đây giúp bảo tồn di sản phi vật thể?
Nguồn gốc của các loại vật nuôi hiện nay là?
Với mô hình động học phân tử, sự khác biệt về độ lớn của lực tương tác giữa các phân tử trong chất rắn, chất lỏng, chất khí dẫn đến sự
Cho tứ diện ABCD. Gọi G là trọng tâm tam giác ABD. Trên cạnh BC lấy điểm M sao cho MB = 2MC. Chọn khẳng định đúng:
Phát biểu nào dưới đây không đúng về các loại thực vật?
Một số amine đồng phân cấu tạo của nhau có công thức phân tử C4H11N. Phát biểu nào sau đây là không đúng về các amine đồng phân này?
a. Ahmed: That's because the ice in the Arctic is melting.
b. Kenji: That's terrible for the polar bears and other animals that live there.
c. Kenji: Why is the ice melting?
d. Ahmed: Because of global warming. The Earth is getting warmer, so the ice is turning to water.
e. Kenji: I saw a picture of a polar bear on a small piece of ice.
