The man standing next to the taxi is tall and heavy-set. He is wearing a yellow shirt and black trousers.

The woman is tall and thin. She has short hair.She is wearing a green skirt and red blouse. She is carrying a bag on her shoulder

The boy sitting on the around looks tired and worried ..He is wearing blue shorts and a white shirt.

The man standing across the street is short and fat. He is wearing blue trousers and a pink shirt and tie. He’s carrying briefcase.

CHÚC BẠN HỌC TỐT! ^^

a, ⁿBaCl₂ = 26 : (137+2.35,5) = 0,125 (mol)

Cứ 1mol BaCl₂ có 1mol Ba, 2mol Cl

\(\rightarrow\) 0,125mol BaCl₂ có 0,125mol Ba, 0,25mol Cl

^mBa = 0,125.137 = 17,125 (g)

^mCl = 26-17,125 = 8,875 (g)

b, ⁿMnCl₂ = 7,56 : (55+2.35,5) = 0,06 (mol)

Cứ 1mol MnCl₂ có 1mol Mn, 2mol Cl

\(\rightarrow\) 0,06mol MnCl₂ có 0,06mol Mn, 0,12mol Cl

^mMn = 0,06.55 = 3,3 (g)

^mCl = 7,56-3,3 = 4,26 (g)

c, ⁿAgNO₃ = 105,4 : (108+14+3.16) = 0,62 (mol)

Cứ 1mol AgNO₃ có 1mol Ag, 1mol N, 3mol O

\(\rightarrow\) 0,62mol AgNO₃ có 0,62mol Ag, 0,62mol N, 1,86mol O

^mAg= 0,62.108 = 66,96 (g)

^mN = 0,62.14 = 8,68 (g)

^mO = 105,4-66,96-8,68 = 29,76 (g)

d, ⁿZn(NO₃)₃ = 37,8 : (65+3.14+9.16) ~ 0,15 (mol)

Cứ 1mol Zn(NO₃)₃ có 1mol Zn, 3mol N, 9mol O

\(\rightarrow\) 0,15mol Zn(NO₃)₃ có 0,15mol Zn, 0,45mol N, 1,35mol O

^mZn= 0,15.65 = 9,75 (g)

^mN = 0,45.14 = 6,3 (g)

^mO = 37,8-9,75-6,3 = 21,75 (g)

e, ⁿAl2(SO4)3 = 34,2 : (2.27+3.32+12.16) = 0,1 (mol)

Cứ 1mol Al₂(SO₄)₃ có 2mol Al, 3mol S, 12mol O

\(\rightarrow\) 0,1mol Al₂(SO₄)₃ có 0,2mol Al, 0,3mol S, 1,2mol O

^mAl = 0,2.27 = 5, 4(g)

^mS = 0,3.32 = 9,6 (g)

^mO = 34,2-5,4-9,6 = 19,2 (g)

CHÚC BẠN HỌC TỐT ! ^^

1, ^PTKAl₂(SO₄)₃ = 2.27+3.(32+4.16) = 342

2, ^PTKNO₃ = 14+3.16 = 62

3,^PTKPO₄ = 31 + 4.16 = 95

4,^PTKCuO = 64 + 16 = 80

5,^PTKHCl = 1+35,5 = 36.5

6,^PTKFe₂O₃ = 2.56+3.16 = 160

7,^PTKMgCl₂ = 24+2.35,5 = 95

8,^PTKCaCO₃ = 40+12+3.16 = 100

9,^PTKH₂SO₄ = 2.1+32+4.16 = 98

10,^PTKH₂O = 2.1+16 = 18

CHÚC BẠN HỌC TỐT ^^

(29) did you do

(30) spent

(31) had just returned

(32) have never been

(33) lived

(34) Are you enjoying

(35) is

(36) don't have

(37) Do you decide

(38) already invited

1.Elderly people were helped often

2.Homeless children were donated some books

3.Them were provided with come medicine

4.I was taken to school everyday

1. Her name is Linh and she's from China

..........T............

2 Linh think Chinese food is delicious.

...........T............

3. People in China always use knives and fork to eat.

............F............

4. Chinese people fry or steam a lot of their food.

.........T............

5. It's rude to take the last piece of food from a serving dish.

...........T.............

6. People usually use naapkins in China.

...........F............

1. He often ........goes............ (go) to school on foot.

2. It ......is raining.............(rain) very hard now.

3. The sun ..........warms.........(warm) the air and .........gives..........(give) us light.

4. Look! A man .........is running..........(run) after the train.

5. She ........goes...........(go) to school everyday.

6. Bad students never ..........work.........(work) hard.

7. It often .........rains..........(rain) in the summer. It .......is raining............(rain) now.

8. The teacher always .........points..........(point) at the black – board when he .......wants............(want) to explain something.

9. Mother ........is cooking...........(cook) some food in the kitchen at the moment, she always ..........cooks.........(cook) in the morning.

10. I always ........meet...........(meet) him on the corner of this street.

11. Where are you .........going...........(go) now? – I ........am going...........(go) to the theater.

12. He ....doesn't...............(not do) morning exercises regularly.

13. Does he ................do........................(do) morning exercises now?

14. Water ........boil...........(boil) at 100 degrees centigrade.

15. He .......will meet.......... (meet) the dentist next week.

16. Are You..........................(be) a good student?

17. They ....don't.... usually ......go....... (not go) to school by motorbike.

18. He ......is swimming......... (swim) overthere now.

19. She .........will come........(come) here next month.

20. They .......aren't............. (not be) doctors.

CHÚC BẠN HỌC TỐT ! :)

I. Viết lại câu sau sao cho nghĩa không đổi.

1. Nam cycles very safely. -> Nam is safe cycler

2. Our vacation lasts three months. -> It’s a three-month vacation

3. Whose book is this? -> Who does this book belong to ?

4. He spent two hours playing games. -> It took him two hours to play games

5. He can’t finish the work on time because he is ill. -> Because of his illness he can't finish the work on time

6. If you don’t work hard, you won’t pass the exam. -> Unless you don't work hard, you will pass the exam

7. How long is the Mekong River? -> What’s the length of Mekong River ?

8. Lan didn’t come to school. And Mai didn’t come to school. -> Neither did Mai

9. How heavy was your brother last time? -> How much weight did your brother last time?

10. Your shirt is very nice. -> What is nice shirt !

II. Cho dạng đúng của từ in hoa.

1. Eating sensibly is the key to good health. SENSIBLE

2. Did you make a decision go to Nha Trang? DECIDE

3. My headache disappeared after I took the tablet. APPEAR

4. Hoa is the best student in her school. GOOD

5. The energetic boys often play soccer. ENERGY.

III. Chia động từ trong ngoặc cho phù hợp thì.

1. What do you (think) think Nam (do) does ? He (tell) tells the truth to his parents

2. When I (come) came to your house yesterday, no one (be) was at home.

3. He (help) will help you fix your bike as soon as he (finish) finish his work.

4. What is your vacation plan (be) now ? I (spend) am going to spend two weeks on a farm.

5. Mai gets used to (stay) staying up late.

IV. Điền vào mỗi chỗ trống một từ cho thích hợp.

Many people (1) prefer to live in big cities, but (2) others prefer living in the (3) countryside . My uncle and aunt have a small (4) house near my home town. They bought it (5) about five years ago. At the side of the farm house, there is a (6) small garden . In it, apple - trees are (7) grew. The vegetable is at the back (8) of the house. My uncle and aunt grow all (9) kinds of vegetables, but they (10) are especially fond of potatoes and tomatoes.

V.Dùng từ gợi ý sau để viết thành câu hoàn chỉnh.

1. She / at home / yesterday/ because / sick.

She was at home yesterday because she was sick.

2. There / be / post office / here / ?

Are there post office here ?

3. Could / tell / how / get / supermarket / please / ?

Could you tell me how to get to supermarket please ?

4. It / difficult / find / apartment / big cities.

It is diffcult to find the apartment in the big cities

5. Teenagers / prefer / listen / lastest pop music / to / folk music.

Teenagers prefer listening lastest pop music to folk music.

1. She isn't playing football, either

2. Sally looks very happy with her new dress

3. "Balanced diet" means you eat a variety of foods without eating to much anything

4.Why does she have work hard every day ?

5.I'm interested in playing chess but I'm not good at it

Phát biểu nào sau đây không đúng

A. Biên độ dao động cưỡng bức phụ thuộc vào quan hệ giữa tần số của ngoại lực và tần số riêng của hệ dao động

B. Biên độ của dao động cưỡng bức phụ thuộc vào biên độ của ngoại lực

C. Tần số của dao động duy trì là tần số riêng của hệ dao động

D. Tần số của dao động cưỡng bức là tần số riêng của hệ dao động