V, Supply the correct form of the words in brackets:

1, Keeping food for long periods was ____________ a huge problem. (history)

2, When you are overwhelmed with ____________ and fright, you will inevitably hesitate to make decisions and take action. (suspect)

3, In 1884, a small ____________ firm was established in a part of Manchester. (engineer)

4, Ever since the discovery of the first pyramid, scientists have wondered how ancient Egyptians built these ____________ structures. (monument)

5, A global ____________ of people’s diets shows that many people eat too much sugar. (analyze)

6, Steve has a strong ____________ for Chinese tea over European tea, which he finds a bit strong. (prefer)

1, Nguyên tử R có tổng số hạt là 28. Số hạt không mang điện bằng \(\dfrac{10}{19}\) lần số khối. Tìm số hiệu nguyên tử và viết kí hiệu nguyên tử R.

1, Hợp chất tạo thành giữa 2 nguyên tử ở trạng thái cơ bản có cấu hình electron lớp ngoài cùng là 3s2 và 2s22p5 thì liên kết giữa chúng sẽ là: 

A. Liên kết cộng hóa trị có cực.

B. Liên kết cộng hóa trị không có cực.

C. Liên kết ion.

D. Liên kết kim loại.

2, Nguyên tử khi tham gia liên kết đã thu thêm 2 electron để thành ion có cấu hình electron 1s22s22p6 là nguyên tử: 

A. Ne           B. Na         C. Mg            D. O

3, Cho biết độ âm điện của các nguyên tố như sau: Cl = 3,0; Na = 0,9; Ca = 1,0; Mg = 1,2; C = 2,5 và O = 3,5. Nhóm gồm những hợp chất có liên kết ion là: 

A. CaO, NaCl, MgCl2.

B. Na2O, CO, CCl4.

C. CaCl2, Na2O, CO2.

D. MgO, Cl2O, CaC2.

4, Xác định số oxi hóa của S trong các hợp chất sau: H2S, S, H2SO3, SO2, SO3:

A. -2; 0; +4; +4; +6

B. +2; 0; +2; +4; +6

C. 0; 0; +2; +4; +6

D. +2; 0; +2; +4; +4

5, Xác định số oxi hóa của Cl trong các phân tử sau: HCl, HClO, NaClO2, HClO3, HClO4.

A. -1; +1; +3; +5; +7

B. -1; +1; +4; +5; +7

C. -1; +1; +3; +5; +6

D. -1; +1; +3; +6; +7

1. Xác định số oxi hóa của lưu huỳnh, clo, mangan và nitơ trong các chất và ion sau:
a) H2S, S, H2SO3, H2SO4, SO2, SO3.      
b) HCl, HClO, NaClO2, HClO3, HClO4.

1, Cộng hóa trị của N trong N2O3 và N2O5 theo thứ tự là

A. 3+ và 5+.       B. 3 và 5.       C. 3 và 4.      D. 3+ và 4+.

2, Số oxi hóa của nitơ trong NH4+, N2O, NO2-, HNO3 lần lượt là :

A. +3, +2, -3, +5.       B. +3, +1, -3, +5.      C. -3, +1, +3, +5.     D. -3, +2, +3, +5.

3, Số oxi hóa của nitơ trong NH4+, NO2- và HNO3 lần lượt là:

A. +5, -3, +3          B. -3, +3, +5          C. +3, -3, +5       D. +3, +5, -3

• Complete the sentences with the correct form of the words in brackets:

1. The experiments we did in the laboratory last week were all very ______________ . (succeed) 

2. Finding a cure for the disease turned out to be much more ______________ than the scientists expected. (challenge) 

3. Important ______________ research is carried out in the laboratories of the university. (science) 

4. If you are doing things in the right way, the results of the experiment with those chemicals should be ______________ . (predict) 

5. To be a good scientist, you need to have a ______________ mind. (logic) 

6. The scientific team needed to present their results in a way that was ______________ to the non-expert. (access) 

7. I’m not ______________ that this latest invention will make people’s lives better. (convince) 

8. Some things can appear to be quiet ______________ until scientists explain them to us. (mystery) 

I) Toán tìm số hạt đủ dữ kiện.

+ Xác định số hạt p, n, e cấu tạo nên nguyên tử:

1. Tổng số hạt là 34, số hạt mang điện nhiều hơn số hạt không mang điện là 10.

2. Tổng số hạt là 126, số nơtron nhiều hơn số e là 12 hạt.

• Read the texts about five people working with animals and the questions below. For each question choose the correct person. The people may be chosen more than once.

A. Veterinary surgeon – Seb Prior

Seb sees a huge variety of creatures in his role as a veterinary surgeon. He says, “Anything can come through the door; you just wouldn’t believe it. We do general pet care and, because the clinic’s so close to a road, I spend lots of time dealing with animals who’ve been hit by cars. I spend half my day in the clinic and a half doing operations, which is a nice mix. I like being able to get out and reach people – being able to talk to them and answer their questions is a huge part of the job. You can be the best surgeon in the world but if you can’t talk to the clients, that’s a huge problem. You need patience and understanding for the people and the animals.”

B. Wildlife assistant – Wendy Burrows

Wendy sees all sorts of animals, from garden birds to tiny hedgehogs and fully-grown swans and every day is different, but Wendy’s wildlife center is particularly busy during the summer months. She looks after up to 500 hedgehogs and their young, who have to reach a certain weight before they can be let go into the wild. Wendy says, “It’s always a lovely moment when this happens, one of the most satisfying parts of the job”, but if this isn’t achieved by September, the hedgehogs have to be kept at the center over the winter period.”

C. Animal care assistant – Anna Lindley

Anna Lindley cares for a wide range of animals, from dogs and cats to birds and mice and it is these smaller animals that give her the greatest satisfaction. “Ever since I was a child, I’ve loved animals and I hate it that we often don’t pay attention to the small ones.” Caring for such a range of animals provides an interesting challenge and plenty of work! “With so much to do, I find myself rushing from job to job and never quite keeping up. I love the fact that you never know what you’re going to get, although unfortunately, that does mean I sometimes have to deal with a snake, which I find a bit scary!”

D. Inspector – Justin Stubbs 

“Becoming an animal inspector was something I’d always wanted – along with being a policeman. At first, I had no idea what it involved but actually, the job is better than I ever imagined. There’s never a day when I don’t want to go to work. The job is a lot harder than people realize and it can get me down at times. Over the years I’ve had to learn to put it to the back of my mind when I leave at the end of the day, but that’s easier said than done and it’s true to say that a bit of the job always comes home with me. It’s the nature of the job.”

E. Vet nurse – Naomi Killingsworth 

Naomi works with people as much as animals but not everyone who comes through the hospital doors is as grateful as you might think, as Naomi explains: “Sometimes I wish more people appreciated what we do. We work hard here, but not everyone realizes that. Of course, there are also many people who couldn’t be more grateful for what we’ve done to help their animals – they make it all worthwhile.”

^{+ QUESTIONS:}

1, Which person is pleased with their schedule at work? ___________

2, Which person says their job was a childhood ambition? ___________

3, Which person does a job in which the amount of work varies?  ___________

4, Which person always looks forward to going to work? ___________

5, Which person says communication is an essential skill for their work? ___________

6, Which person is disappointed by some people’s opinion of their work? ___________

7, Which person prefers working with a certain kind of animal? ____________