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3 tháng 8 2021

If John is late, we will wait for him.

If it rains, we will cancel the trip

If I have time, I will watch a movie.

If we don't hurry up, we will miss our flight.

Katy will be mad if Sam is late again.

Last night I played my guitar loudly and the neighbors complained.

She kissed me on the cheek.

It rained yesterday.

Angela watched TV all night.

John wanted to go to the museum.

We were just talking about it before you arrived. 

He wasn’t working when his boss came yesterday.

Was your mother going to the market at 7 A.M yesterday? 

When I was singing in the bathroom, my mother came in.

The man was sending his letter in the post office at that time.

It has been 2 months since I first met him.

I have watched TV for two hours. 

 She has prepared for dinner since 6.30 p.m. 

He has eaten this kind of food several times before.

Have you been to that place before? 

They have worked for this company for 5 years

3 tháng 8 2021

Đk loại 1

If I am hungry, I will get something to eat.

If I don’t see him this afternoon, I will phone him in the evening. 

If it rains we may get wet

If John has the money, he will buy a Ferrari 

She’ll be cold if she doesn’t wear a coat

Quá khứ đơn:

I was at my uncle’s house yesterday afternoon.

They didn’t accept our offer. 

We vistied Australia last summer

Did Cristiano play for Manchester United

What did you do last Sunday?

Quá khứ tiếp diễn:

He was cooking dinner at 4 p.m yesterday.

They were playing soccer when I came yesterday

He wasn’t working when his boss came yesterday.

We weren’t watching TV at 9 p.m yesterday. 

Was your mother going to the market at 7 a.m yesterday?

Hiện tại hoàn thành:

I have watched TV for two hours

She has prepared for dinner since 6.30 p.m

 He has eaten this kind of food several times before. 

We haven’t met each other for a long time. 

He hasn’t come back to his hometown since 2000.

8 tháng 7 2021

1 send - will receive 

2 do - will improve

3 find - will give

4 will go - has

5 will go - gets

6 doesn't phone - will leave

7 don't study - won't pass

8 rains - won't have to

9 won't be able to - watch

10 cann't move - isn't

11 study - will pass

12 shines - will walk

13 has - will see

14 come - will be

15 earns - will fly

16 travel - will visit

17 wear - will slip

18 forgets - will give

19 go - will listen

27 tháng 10 2021

Câu 3 : 

\(S\underrightarrow{1}SO_2\underrightarrow{2}SO_3\underrightarrow{3}H_2SO_4\underrightarrow{4}BaSO_4\)

(1) \(S+O_2\underrightarrow{t^o}SO_2\)

(2) \(2SO_2+O_2\underrightarrow{t^o,V_2O_5}2SO_3\)

(3) \(SO_3+H_2O\rightarrow H_2SO_4\)

(4) \(H_2SO_4+BaCl_2\rightarrow2HCl+BaSO_4\)

 Chúc bạn học tốt

27 tháng 10 2021

\(\left(1\right)S+O_2\rightarrow^{\left(t^0\right)}SO_2\\ \left(2\right)2SO_2+O_2\rightarrow^{\left(t^0,V_2O_5\right)}2SO_3\\ \left(3\right)SO_3+H_2O\rightarrow H_2SO_4\\ \left(4\right)H_2SO_4+BaO\rightarrow BaSO_4+H_2O\)

13 tháng 10 2021

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

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

\(SO_3+H_2O\rightarrow H_2SO_4\)

\(H_2SO_4+BaO\rightarrow BaSO_4+H_2O\)

13 tháng 10 2021

Câu 3 : 

\(S\underrightarrow{1}SO_2\underrightarrow{2}SO_3\underrightarrow{3}H_2SO_4\underrightarrow{4}BaSO_4\)

(1) \(S+O_2\underrightarrow{t^o}SO_2\)

(2) \(2SO_2+O_2\underrightarrow{t^o,V_2O_5}2SO_3\)

(3) \(SO_3+H_2O\rightarrow H_2SO_4\)

(4) \(H_2SO_4+BaCl_2\rightarrow2HCl+BaSO_4\)

 Chúc bạn học tốt

27 tháng 10 2021

Câu 3 : 

\(Ca\underrightarrow{1}CaO\underrightarrow{2}Ca\left(OH\right)_2\underrightarrow{3}CaCO_3\underrightarrow{4}CO_2\)

(1) \(Ca+O_2\underrightarrow{t^o}CaO\)

(2) \(CaO+H_2O\rightarrow Ca\left(OH\right)_2\)

(3) \(Ca\left(OH\right)_2+CO_2\rightarrow CaCO_3+H_2O\)

(4) \(CaCO_3\underrightarrow{t^o}CaO+CO_2\)

 Chúc bạn học tốt

13 tháng 10 2021

\(Ca+\dfrac{1}{2}O_2\rightarrow CaO\)

\(CaO+H_2O\rightarrow Ca\left(OH\right)_2\)

\(Ca\left(OH\right)_2+CO_2\rightarrow CaCO_3+H_2O\)

\(CaCO_3\xrightarrow[]{t^o}CaO+CO_2\)

13 tháng 10 2021

PT(1) cần nhiệt độ

12 tháng 4 2023

1)

a)

$C_2H_4 + H_2O \xrightarrow{t^o,xt} C_2H_5OH$
$C_2H_5OH + O_2 \xrightarrow{men\ giấm} CH_3COOH + H_2O$

$CH_3COOH + NaOH \to CH_3COONa + H_2O$

b)

$CH_3COOH + C_2H_5OH \buildrel{{H_2SO_4}}\over\rightleftharpoons CH_3COOC_2H_5 + H_2O$

2)

a) $n_{CO_2} = \dfrac{16,8}{22,4} = 0,75(mol)$
$C_6H_{12}O_6 \xrightarrow{men\ rượu} 2CO_2 + 2C_2H_5OH$
$n_{glucozo} = \dfrac{1}{2}n_{CO_2} = 0,375(mol)$
$m_{glucozo} = 0,375.180 = 67,5(gam)$

b) $n_{C_2H_5OH} = n_{CO_2} = 0,75(mol)$
$m_{C_2H_5OH} = 0,75.46 = 34,5(gam)$

$V_{C_2H_5OH} = \dfrac{34,5}{0,8}=  43,125(ml)$

12 tháng 4 2023

Câu 1:

a, \(C_2H_4+H_2O\underrightarrow{t^o,xt}C_2H_5OH\)

\(C_2H_5OH+O_2\underrightarrow{mengiam}CH_3COOH+H_2O\)

\(CH_3COOH+Na\rightarrow CH_3COOH+\dfrac{1}{2}H_2\)

b, \(CH_3COOH+C_2H_5OH⇌CH_3COOC_2H_5+H_2O\) (xt: H2SO4 đặc, to)

Câu 2:

a, \(n_{CO_2}=\dfrac{16,8}{22,4}=0,75\left(mol\right)\)

\(C_6H_{12}O_6\underrightarrow{t^o,xt}2C_2H_5OH+2CO_2\)

Theo PT: \(n_{C_6H_{12}O_6}=\dfrac{1}{2}n_{CO_2}=0,375\left(mol\right)\)

\(\Rightarrow m_{C_6H_{12}O_6}=0,375.180=67,5\left(g\right)\)

b, \(n_{C_2H_5OH}=n_{CO_2}=0,75\left(mol\right)\Rightarrow m_{C_2H_5OH}=0,75.46=34,5\left(g\right)\)

\(\Rightarrow V_{C_2H_5OH}=\dfrac{34,5}{0,8}=43,125\left(ml\right)\)