Giúp mình với ạ, mình đang cần gấp :< mình cảm ơn ạaaa
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1. How many kilos of potatoes would you like?
2. I went fishing but I didn't catch any fish.
3. Cook the chicken over low heat for 15 minutes before you serve it.
4. Can you tell me how to cook broken rice?
5. There are three cartons of milk in the fridge.
6. He has an egg but he hasn't got any bread.
7. Pho is one of the most popular dishes in Vietnam.
1) \(\left(\dfrac{-13}{17}-\dfrac{31}{52}\right)-\left(\dfrac{73}{52}-\dfrac{13}{17}+\dfrac{5}{6}\right)-\dfrac{3}{4}\)
\(=\dfrac{-13}{17}-\dfrac{31}{52}-\dfrac{73}{52}+\dfrac{13}{17}-\dfrac{5}{6}-\dfrac{3}{4}\)
\(=\left(\dfrac{-13}{17}+\dfrac{13}{17}\right)-\left(\dfrac{31}{52}+\dfrac{73}{52}\right)-\left(\dfrac{5}{6}+\dfrac{3}{4}\right)\)
\(=0-2-\dfrac{19}{12}\)
\(=-2-\dfrac{19}{12}\)
\(=\dfrac{-43}{12}\)
PTHH: Al2O3+6HCl➝2AlCl3+3H2O(1)
a)nAl2O3=\(\dfrac{10,2}{102}\)=0,1(mol)
mHCl=\(\dfrac{5\%.219}{100\%}\)=10,95(g)
⇒nHCl=\(\dfrac{10,95}{36,5}\)=0,3(mol)
Xét tỉ lệ Al2O3:\(\dfrac{0,1}{1}\)=0,1
Xét tỉ lệ HCl:\(\dfrac{0,3}{6}\)=0,05
⇒HCl pứng hết,Al2O3 còn dư
Theo PTHH(1) ta có nAl2O3 pứng=\(\dfrac{nHCl}{6}\)=\(\dfrac{0,3}{6}\)=0,05(mol)
⇒nAl2O3 dư=nAl2O3ban đầu-nAl2O3 pứng=0,1-0,05=0,05(mol)
⇒mAl2O3 dư=0,05.102=5,1(g)
b) C%HCl=\(\dfrac{0,3.36,5}{219+10,2}\).100%=4,8%
nAlCl3=0,1(mol)
⇒C%AlCl3=\(\dfrac{0,1.136,5}{10,2+219}\).100%=6%
Mình làm không biết đúng không. Bạn thông cảm
27. instruction
28. fashionable
29. Religious
30. Proud
31. enjoyable
32. restful
33. interesting
34. interested
35. entrance
36. picnicking
37. heroes
38. enjoyably - rested
40. enjoyment
41. villagers
42. relaxing
43. restful
44. collection
45. difficulties
46. improvement
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48. advertisement
49. qualification
50. do not practice - will not get
51. spending
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53. speaker
54. got - sleeping
55. invention
56. informative - entertaining
57. popular
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59. viewers
60. inconvenience
61. costly - consuming
62. pitiful
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64. communication
65. informative
66. interaction
67. popular
68. being widened
69. interesting
70. inventor
71. quality
72. development
73. peaceful
74. economical
75. separatism
76. impressing
77. friendless
78. religion
79. interested
80. qualified
81. impolite/unpolite
82. relaxing
83. reputation
84. hurriedly