\(PTHH:\)

\(2Na(0,2)+2H_2O--->2NaOH(0,2)+H_2(0,1)\)

\(n_{Na}=\dfrac{4,6}{23}=0,2\left(mol\right)\)

\(n_{H_2O}=11,11\left(mol\right)\)

\(\Rightarrow\)Chon số mol của Na để tính.

Dung dich thu được là NaOH

Theo PTHH: \(n_{NaOH}=0,2\left(mol\right)\)

\(\Rightarrow m_{NaOH}=40.0,2=8\left(g\right)\)

\(n_{H_2}=0,1\left(mol\right)\)

\(\Rightarrow m_{H_2}=0,2\left(g\right)\)

\(m_{ddsau}=m_{Na}+m_{H_2O}-m_{H_2}\)

\(\Leftrightarrow m_{ddsau}=4,6+200-0,2=204,4\left(g\right)\)

Nồng độ phần trăm của dung dịch sau phản ứng:

\(C\%NaOH=\dfrac{8}{204,4}.100\%=3,91\%\)

Câu 1)

\(3Fe(0,45)+2O_2(0,3)-t^o->Fe_3O_4\)\((1)\)

\(nFe=\dfrac{25,2}{56}=0,45\left(mol\right)\)

Theo PTHH (1): \(nO_2=0,3\left(mol\right)\)

\(2KClO_3(0,2)-(t^o,MnO_2)->2KCl+3O_2(0,3)\)\((2)\)

Theo PTHH (2) \(n_{KClO_3}=0,2\left(mol\right)\)

khoi luong KClO3 can dung de thu duoc the tich O2 như phản ứng trên.:

\(\Rightarrow m_{KClO_3}=0,2.122,5=24,5\left(g\right)\)

Part II. Supply the correct form or tense of the verbs in the parentheses (3.0 points).

1. Where is your mother? – She is in the kitchen. She __is cooking____(cook) the dinner.

2. Your brother often __Did your brother often go____ (go) to school by bus last year?

3. He often played football when he ( be ) .........was............young .

4. Trung is learning to play the guitar. He ( have ) ......has.............guitar lessons twice a week.

5. Look! The plane (fly) .........is flying................... toward to the airport. It (land)........is landing..................

6. Take these medicines and you ( feel ) ............will feel........ better then, Ha .

7. I .....will have.........(have) a birthday party tomorrow evening. Would you like ....to come.......(come)?

8. ......Does he like...... he (like) milk or tea?

9. Where is Nam?- He(watch)..........is watching.............. TV in his room at the moment.

10. I often go to school by bicycle but today I ......go..... (go) to school by bus.

11. My best friend (write).............writes................. me a letter several time.

12. If it (be ) ......is........nice tomorrow. We ( plant)...........will plant............some young trees.

13. - .......Have............you ever ( see ).........seen...........a real robot at work?

- No, never.

14. Do you think there ( be ) .........is.........a city underwater?

15. I (never ,see)..............have never seen...............such a big flower.

16. He ( never meet ) .........have never met...........her before.

Part III. Give the correct form of the words in brackets. (2.0 points)

EX. Knowing English well is very (use ).....useful... -> useful

1. The .......length......... of the experiment is about 20 minutes (LONG)

2.She sent her best wishes for my future...... happiness........(HAPPY)

3. The ......leaves.........of this tree are very green and beautiful. ( LEAF )

4. Every year I make a .........resolution...............and every year I break it. (RESOLUTE)

6. That's a..............creative...............designer. She has a lot of new ideals.(CREATE)

7. Nhung is quiet,but sometimes she becomes.......talkative........(TALK)

8. They're famous football..............player.................. (PLAY)

9. They are ...........talking................ about their lesson. (TALK)

10. She told me she would comes so be.....patient...........(PATIENCE)

Part IV. Each sentence below contains an error. Underline it and write the correct answer in the space provided. (2.0 points)

1. I have learnt how swim since 2010. => to swim

2. She has worked for this bank since she leaves university.=> left

3. What sweet voice you have! => how

4. I go to the school library to borrow books twice.

5. Could you tell me the way to the post office ? => can

6. I received a letter to my friend last week.=> from

7. I have gone to Singapore three times.=> been

8. My brother can't swim, so he is afraid of water.=> because

9. Don't eat too much salt because it is not good to you.=> for

10.- "Which is the most expensive city in the world ?" – " I think it's Tokyo." => What

Kim usually (go)..goes.....to school by bike. But today she(walk)......walks.......to school.

I. Chọn từ phát âm khác với các từ còn lại:

A. aunt \([a:]\)

B. nature \([ei]\)

C. tomato \([a:]\)

D. garden \([a:]\)

\(a)\)

Ở \(20^o C\), độ tan của muối NH4Cl là 37,2 g.

Tức là có 37,2 gam NH4Cl tan tối đa trong 100 g H2O để tạo thành dung dich bão hòa ở \(20^o C\)

\(\Rightarrow m_{ddNH_4Cl}=137,2\left(g\right)\)

\(\Rightarrow\)Trong 300 g dung dich MH4Cl bão hòa có:

\(m_{NH_4Cl}=\dfrac{300.37,2}{137,2}=81,34\left(g\right)\)

\(b)\)

Độ tan của muối ăn (Nacl) ở 20°C là 26g

Tức là có 26 g NaCl tan tối đa trong 100 gam H2O để tạo thành dung dich bão hòa ở \(20^o C\)

\(\Rightarrow m_{ddNaCl}=126\left(g\right)\)

nồng độ phần trăm của dung dịch bão hoà ở nhiệt độ trên.

\(C\%_{NaCl}=\dfrac{26}{126}.100\%=20,63\%\)

\(2M+2H_2O--->2MOH+H_2\)

\(nM=\dfrac{4,6}{M}(mol)\)

\(nH_2=0,1(mol)\)

Theo PTHH: \(n_M=2.n_{H_2}\)

\(\Leftrightarrow\dfrac{4,6}{M}=0,2\)

\(\Rightarrow M=23\)

Vậy kim loại kiềm cần tìm là Na

Chọn A

\(1)\)\(2NaCl+2H_2 O-(đ p d d , màn ngăn xốp)->2NaOH+Cl_2+H_2\)

\(2)\)\(CaCO_3-t^o->CaO+CO_2\)

\(3)\)\(2H_2O-điện phân>2H_2+O_2\)

\(4)\)\(2NaOH+CO_2--->Na_2CO_3+H_2O\)

\(5)\)\(NaOH+CO_2--->NaHCO_3\)

\(6)\)\(4NaOH+3CO_2--->Na_2CO_3+2NaHCO_3+H_2O\)

\(7)\)\(CaO+H_2O--->Ca(OH)_2\)

\(8)\)\(Cl_2+H_2-(ánh sáng,t^o)->2HCl\)

\(9)\)\(Na_2CO_3+CO_2+H_2O--->2NaHCO_3\)

\(10)\)\(CaCO_3+2HCl--->CaCl_2+CO_2+H_2O\)

\(11)\)\(CaO+2HCl--->CaCl_2+H_2O\)

III Change these sentences into reported

1."Is these a phone"

-> I asked her..if there was a phone....................................

2."Do you have many friends ?"

->She asked me ..if I had many friends...................................

3."Is there a fridge in the kitchen?"

->I asked her ....whether there was a fridge inthe kitchen........................................

4."Do you smoke?"

->She asked me...if i smoked................................................................

5."Does the flat have central heating?"

->I asked her .....if the flat had central heating..............................................................................

lifter/ heavy/so/is/and/he/a/strong/weight/very/he/is/./

\(\Rightarrow\) He is a weight lifter so he is very sstrong and heavy