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uyen
14 phút trước
I agree with the above opinion, because I think that using bicycles to go to school will help us shorten the time to go to school instead of walking. It is very convenient. If you ride a bicycle to school, your parents won't have to worry about driving you to school on time and you think so too, right? Cycling to school is not only convenient, but in going out, eating, working, you can also use a bicycle. Due to the small bicycle area, you can wriggle through the small alleys. And that's my pers...
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Pham Minh Tue
12 phút trước
I used to think the same way,too .But after I heard my teacher explain the uses of the electric bike last week,I had some different thoughts.Electric bike have both positive and negative sides.On the good side,it to protect the environment,it doesn't produce smoke.It also smooth when driving.On the bad side,it makes students get lazy.They don't walk but drive for a short distance and that'll cost them money.So,in my opinion,electric bike is very useful,but it will be harmful if you depend on it...
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Khánh Linh Hoàng
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Kudo Shinichi
20 phút trước

$\rm Fe + 2HCl \rightarrow FeCl_2 + H_2$
$\rm FeCl_2 + 2KOH \rightarrow Fe(OH)_2 \downarrow + 2KCl$
$\rm Fe(OH)_2 \xrightarrow[\text{chân không}]{t^o} FeO + H_2O$
$\rm FeO + H_2 \xrightarrow{t^o} Fe + H_2O$
$\rm 2Fe + 3Cl_2 \xrightarrow{t^o} 2FeCl_3$
$\rm FeCl_3 + 3NaOH \rightarrow Fe(OH)_3 \downarrow + 3NaCl$
$\rm 2Fe(OH)_3 \xrightarrow{t^o} Fe_2O_3 + 3H_2O$
$\rm Fe_2O_3 + 3CO \xrightarrow{t^o} 2Fe + 3CO_2$

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Dương Minh Huy
18 phút trước
\(Fe+2HCl\xrightarrow[]{}FeCl_2+H_2\)\(FeCl_2+2NaOH\xrightarrow[]{}Fe\left(OH\right)_2+2NaCl\)\(Fe\left(OH\right)_2\xrightarrow[]{t^o}FeO+H_2O\)\(FeO+H_2\xrightarrow[]{t^o}Fe+H_2O\)\(2Fe+3Cl_2\xrightarrow[]{t^o}2FeCl_3\)\(FeCl_3+3KOH\xrightarrow[]{}Fe\left(OH\right)_3+3KCl\)\(2Fe\left(OH\right)_3\xrightarrow[]{t^o}Fe_2O_3+3H_2O\)\(Fe_2O_3+3CO\xrightarrow[]{t^o}2Fe+3CO_2\)
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Diana=0
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Mèo Dương
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Đông Hải
17 phút trước
19, Jean cloth was made completely from cotton in the \(18^{th}\) century20, You can write an English letter, can't you?21, The last time everybody saw Tom was a week ago.22, The English test will be taken by all the students of the ninth form next week.23, Our teeth should be brushed carefully after meals.24, The traffic rules must be observed strictly25, Their homework was done well.26, I wish I didn't have to do homework every night.
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NV Tr
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NV Tr
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A sceneries

sceneries:những phong cảnh

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Duy Nguyễn
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