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

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

\(SO_3+H_2O\rightarrow H_2SO_4\)

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

\(SO_2+H_2O⇌H_2SO_3\)

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

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

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

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

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

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

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

32. is covered

33. was held

34. are followed

35. hasn't visited, moved

36. has been used

37. are destroyed

38. is getting

39. visit, was doing

40. is celebrated

41. is visited

14:

a: Để hai đường cắt nhau trên trục tung thì m-1=15-3m

=>4m=16

=>m=4

b: Khi m=4 thì (d1): y=-4x+3 và (d2): y=4/3x+3

Tọa độ A là:

y=0 và -4x+3=0

=>x=3/4 và y=0

Tọa độ B là:

y=0 và 4/3x+3=0

=>x=-3:4/3=-9/4 và y=0

c: C(0;3); A(3/4;0); B(-9/4;0)

AB=căn (-9/4-3/4)^2+(0-0)^2=3

AC=căn (3/4-0)^2+3^2=3/4*căn 17

BC=căn (-9/4-0)^2+(3-0)^2=15/4

\(cosA=\dfrac{AB^2+AC^2-BC^2}{2\cdot AB\cdot AC}=\dfrac{\sqrt{17}}{17}\)

=>sinA=4/căn 17

\(S_{ABC}=\dfrac{1}{2}\cdot AB\cdot AC\cdot sinA=\dfrac{9}{2}\)

\(C=3+\dfrac{3}{4}\sqrt{17}+\dfrac{15}{4}=\dfrac{27}{4}+\dfrac{3}{4}\sqrt{17}\)

d: AB=3; AC=3/4*căn 17; BC=15/4

sin A=4/căn 17

=>AB/sinC=AC/sinB=BC/sinA

=>góc A=76 độ; 3/sinC=3/4*căn 17/sinB=15*căn 17/16

=>sin C=16*căn 17/85; sin B=4/5

=>góc B=53 độ; góc C=51 độ

\(n_{H_2}=\dfrac{0,224}{22,4}=0,01\left(mol\right)\\ pthh:2R+2H_2O\rightarrow2ROH+H_2\) 
          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

a: Xét ΔABI và ΔACI có

AB=AC

AI chung

IB=IC

Do đó: ΔAIB=ΔAIC

She thanks me for inviting her to the party.

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Kate is going to tell her younger sister about her trip to Japan.

My sister loves taking care of small animals.

She thanks me for inviting her to the party.

Why's Mr. Grim interested in sitting in a boat and fishing?

Do your classmates do their homework in the library?

Kate is going to tell her younger sister about her trip to Japan
My sister loves taking care of small animals

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