1. Each student …… to answer three questions.
A. have B. has C. having D. to have
2. Plenty of milk …… consumed every day.
A. are B. were C. is D. was
3. SARS …… an epidemic that kills many people in china.
A. are B. were C. have been D. is
4. The little girl with her friends …… coming here.
A. be B. is C. are D. to be
5. The United States …… between Canada and Mexico.
A. lying B. lies C. lain D. lie
6. The book for my English courses …… 25 dollars
A. costed B. costing C. cost D. costs
7. Jane as well as both of you …… finished it.
A. doesn’t B. don’t C. haven’t D. hasn’t
8. Everyone in both cars …… injured in the accident last night.
A. was B. is C. are D. were
9. Ten years of waiting …… nothing to those who are in love.
A. means B. mean C. to mean D. meaning
10.The students in the next classroom …… very loudly every day.
A. talk B. talked C. are talking D. talks
11. Several of students …… absent yesterday.
A. has been B. had been C. were D. was
12. A book or a newspaper …… precious for me when I am free.
A. be B. is C. are D. to be
13. None of the students …… the test yet.
A. have finished B. has finished C. finished D. is finishing
14. The cattle …… in the field now
A. grazing B. grazes C. has grazed D. are grazing
15. Not only his friends but also Tom …… soccer.
A. likes B. like C. is liking D. does like
16. The news …… so bad that she collapsed.
A. are B. was C. were D. have been
17. The police …… for the thieves at the moment.
A. is looking B. are looking C. have been looking D. will be looking
18. …… John nor his friends are going with us.
A. Either B. Together with C. Neither D. Along with
19. The classroom with 10 tables …… 20 chairs in it.
A. has B. have C. is D. are
20. Two tons of coal …… required.
A. are B. is C. have been D. were
21. Economics …… me as much as literature does.
A. interest B. do not interest C. does not interest D. have interested
22. Not only his friends but also Tom …… soccer.
A. likes B. like C. is liking D. does like
23. A number of students in my class …… good at English.
A. is not B. are not C. was not D. has not been
24. Both of the computers …… not working.
A. were B. is C. was D. has been
25. Learning foreign languages …… necessary at all time.
A. are B. will be C. were D. is
26. Money, nor fame, nor wealth …… brought happiness to everybody.
A. has B. have C. are D. were
27. Most of the rooms in the hotel where we are staying …… air conditioning.
A. have B. had C. has had D. has
28. The bottles of wine …… on the shelf.
A. is B. are C. was D. has put
29. I think the teacher as well as his students …… good.
A. is B. are C. be D. to be
30. None of the students …… the vice principal.
A. has seen B .have seen C. is seen D. was seen
31. There …… a lot of expensive furniture in our uncle’s house.
A. have been B. are C. is D. were
32. Each of you …… responsible for this.
A. are B. being C. is D. be
33. Bill together with his brothers …… to the beach every morning.
A. going B. goes C. are D. gone
34. Either the monitor or the athletes …… to blame for the bad result.
A. be B. are C. is D. to be
35. Everyone …… with me about my plans.
A. agree B. agreeing C. disagree D. agrees
36. Tim as well as his relatives …… safe from the hurricane.
A. be B. is C. are D. being
37. The little boy with his friends …… coming here.
A. be B. is C. are D. to be
38. Neither Jane nor her classmates nor her boy friend …… the problem .
A. understands B. understand C. not understand D. understand not
39. The results of Dr. Frank’s experiment …… announced on TV last night.
A. is B. are C. was D. were
40. Fifty minutes …… the maximum length of time allowed for the exam.
A. is B. be C. are D. were
41. Each of the teachers …… a timetable.
A. to have B. have C. having D. has
42. The cost of living …… over 10% in the last few years.
A. rises B. has risen C. rose D. is rising
43. Neither the teacher nor the students …… happy about the test results.
A. are B. is C. has D. have
44. A number of sheep …… eating grass now.
A. is B. are C. was D. were
45. Measles …… sometimes a serious disease.
A. is B. are C. being D. be
46. The effects of cigarette smoking …… been proven to be extremely harmful.
A. has B. have C. is D. are
47. The number of students who …… withdrawn from class this semester …… appalling.
A. has/is B. have/are C. have/is D. has/are
48. The exercise on agreement of subjects and verbs …… easy.
A. are B. have C. has D. is
49. Making cakes and pies …… Mrs. Reed’s specialty.
A. are B. were C. is D. be
50. The United Nations …… about 160 nations.
A. consist of B. consisting C. consist D. consists of
giúp em với ạ
Bài 1:
\(Fe_2O_3+6HCl\rightarrow2FeCl_3+3H_2O\)
\(n_{HCl}=\frac{120.18,25}{100.36,5}=0,6mol\)
\(\rightarrow n_{Fe_2O_3}=\frac{1}{6}n_{HCl}=0,1mol\)
\(\rightarrow m=m_{Fe_2O_3}=16g\)
\(n_{FeCl_3}=\frac{1}{3}n_{HCl}=0,2mol\)
\(\rightarrow C\%_{FeCl_3}=\frac{0,2.162,5}{16+120}.100\%=23,9\%\)
Bài 2:
\(nMg=\frac{4,8}{24}=0,2mol\)
\(Mg+H_2SO_4\rightarrow MgSO_4+H_2\)
\(mH_2SO_4=0,2.98=19,6g\)
\(m_{ddH_2SO_4}=19,6.\frac{100}{9,8}=200g\)
\(m_{H_2}=0,2.2=0,4g\)
\(m_{dd}\) sau phản ứng \(=mMg+m_{ddH_2SO_4}-m_{H_2}=4,8+200-0,4=204,4g\)
\(m_{MgSO_4}=0,2.120=24g\)
\(C\%MgSO_4=\left(\frac{24}{204,4}\right).100=11,74\%\)
Bài 3:
\(2Al+6HCl\rightarrow2AlCl_3+3H_2\)
\(Al_2O_3+6HCl\rightarrow2AlCl_3+3H_2O\)
\(n_{H_2}=0,15mol\)
\(\rightarrow n_{Al}=\frac{2}{3}n_{H_2}=0,1mol\)
\(n_{AlCl_3}=0,3mol\)
\(\rightarrow n_{Al+2nAl_2O_3}=n_{AlCl_3}=0,3mol\)
\(\rightarrow n_{Al_2O_3}=0,1mol\)
\(\rightarrow a=m_{Al+m_{Al_2O_3}}=0,1.\left(27+102\right)=12,9g\)
\(n_{HCl}=3n_{Al}+6n_{Al_2O_3}=0,9mol\)
\(\rightarrow m_{HCl}=32,85g\)
\(\rightarrow b=m_{HCldd}=\frac{32,85.100}{7,3}=450g\)
\(m_{dd}=12,9+450-0,15.2=462,6g\)
\(\rightarrow C\%_{AlCl_3}=\frac{40,05}{462,6}.100\%=8,66\%\)