2 giờ trước (1:39)

Đáng lẽ phải trừ mH2 nhưng đáp án ko có đúng ko ạ

Bình luận (0)
13 tháng 12 2021 lúc 11:54

45+46. Some people are ……on………….. the mountain and they're…………in……….danger.

47. I am looking ………for………….. some chocolate to buy.

48. The plane flies ………above…………. mountains, rivers, and towns.

49. ……………After……… school, we always go home and play tennis.

50. Are you free…………on………Saturday afternoon ? – Yes, Why?

51. How ………about………going to the cinema?

52. I am going ………to take?……………..my parents to the zoo this Sunday.

53. There aren’t many good programs……for……………..……..teenagers.

54.  Baseball is different .............from.............. soccer.

55.  I walk up a lot of stairs every day. My flat is ……on……..……. the third floor and there is no lift.

56.  He thinks walking to school is good ......for................. him.

57.  It can be dangerous when children play football ………on..……….. the street.

58.  Will you go home ............with............. me?

59.  Mr. Boyle’s office is ……in…………..…. 56 Alley Street.

60.  Shall we go ........out............... tonight?

61.  In most countries, people drive ………on….………. the right.

62.  My sister takes care…………of..……… me when I am sick.

63.  I don’t believe ………in………….…. what she is saying.

64.  Take the bus number 7 and get………off………..…… at the cinema.

65.  I am good………at……………… playing the violin.

66.  I am tired ………of…….……….hearing the noise you make when you are playing the drums. It’s so terrible.

Bình luận (0)
13 tháng 12 2021 lúc 11:53
Bình luận (0)
4 giờ trước (0:07)

ngủ muộn zợ a :((

Bình luận (1)
4 giờ trước (0:26)

a) Gọi số mol N2, O2 trong 6,72l khí A lần lượt là a, b

=> $\left\{{}\begin{matrix}28a+32b=8,8\\a+b=\dfrac{6,72}{22,4}=0,3\end{matrix}\right.$

=> $\left\{{}\begin{matrix}a=0,2\left(mol\right)\\b=0,1\left(mol\right)\end{matrix}\right.$

$\left\{{}\begin{matrix}\%V_{N_2}=\dfrac{0,2}{0,3}.100\%=66,67\%\\\%V_{O_2}=\dfrac{0,1}{0,3}.100\%=33,33\%\end{matrix}\right.$

$\left\{{}\begin{matrix}\%m_{N_2}=\dfrac{28.0,2}{8,8}.100\%=63,64\%\\\%m_{O_2}=\dfrac{32.0,1}{8,8}.100\%=36,36\%\end{matrix}\right.$

b)

$n_A=0,3\left(mol\right)$

$\Rightarrow n_{CO_2}=0,3\left(mol\right)$

$\Rightarrow m_{CO_2}=0,3.44=13,2\left(g\right)$

c) 2,2g A có thể tích là 1,68 lít

=> $V_{H_2}=1,68\left(l\right)$

Bình luận (0)
4 giờ trước (23:59)

<=> x/36 = 27/36 => x = 27

Bình luận (0)
3 giờ trước (0:37)

$\dfrac{x}{36}=\dfrac{3}{4}\Rightarrow x\times4=36\times3\\ =208\\ x=208:4\\ \Rightarrow x=52$

Bình luận (0)