A

C

B

C

A

C

B

C

D

B

1A

2C

3B

4C

5B

6C

7B

8C

9D

10B

1.are learning 

2.teaches

3.went

4.fly

5.Did they buy

1. are learing

2. teaches

3. went

4. fly

5. Did - buy

1. are learning 

2. teaches

3. went

4. fly

5. Did / buy

1. worried

2. boring

3. driver

4. information

5. comfortable

worried

boring

driver

information

comfortable

1. Worried

2. Boring

3. Driver

4. Information

5. Comfortable

1finished

2 are working

3 goes

4 live - have lived

5 left

6 was sitting - began

7 have - seen

8 has worked 

9 flow

10 is smoking

11 was working

12 saw - will remind

13 has done

14 was waiting

15 is writing

16 travels

17 was sitting

18 was studying

19 come - am living

20 was reading - was studying

21 Reading

22 had washed

\(S+O_2\xrightarrow[]{t^o}SO_2\)

\(SO_2+\dfrac{1}{2}O_2\xrightarrow[V_2O_5]{t^o}SO_3\)

\(SO_3+H_2O\rightarrow H_2SO_4\)

\(H_2SO_4+Na_2O\rightarrow Na_2SO_4+H_2O\)

\(SO_2+H_2O⇌H_2SO_3\)

\(2H_2SO_{4\left(đ\right)}+Cu\xrightarrow[]{t^o}CuSO_4+SO_2+2H_2O\)

\(\left(1\right)S+O_2\overset{t^o}{--->}SO_2\)

\(\left(2\right)2SO_2+O_2\xrightarrow[V_2O_5]{t^o}2SO_3\)

\(\left(3\right)SO_3+H_2O--->H_2SO_4\)

\(\left(4\right)H_2SO_4+2NaOH--->Na_2SO_4+2H_2O\)

\(\left(5\right)SO_2+H_2O--->H_2SO_3\)

\(\left(6\right)H_2SO_4+Na_2SO_3--->Na_2SO_4+SO_2\uparrow+H_2O\)

friendly

happy

meeting

impress

widely

\(n_{H_2}=\dfrac{0,224}{22,4}=0,01\left(mol\right)\\ pthh:2R+2H_2O\rightarrow2ROH+H_2\) 
          0,02                                0,01 (mol) 
\(\Rightarrow M_R=0,78:0,02=39\left(\dfrac{g}{mol}\right)\) 
mà R hóa trị I => R là K