số mol ZnO tham gia phản ứng :

n_ZnO = \(\frac{m}{M}\)= \(\frac{16,2}{81}\)= 0,2 mol

theo PTHH ta có:

n_Zn = n_ZnO = 0,2 mol

=> m_Zn = n . M = 0,2 . 65 = 13g

1. \(C_nH_{2n}+\frac{3n}{2}O_2\rightarrow nCO_2+nH_2O\)

2.\(C_nH_{2n}+3N+\frac{3n}{2}O_2\rightarrow nCO_2+nH_2O+\frac{3}{2}N_2\)

3.\(C_nH_{2n}+2O+\frac{3n-2}{2}O_2\rightarrow nCO_2+nH_2O\)

4.\(Fe+CuSO_4\rightarrow FeSO_4+H_2O\)(Phương trình lỗi rồi)

5.\(Al\left(NO_3\right)_3\rightarrow Fe_2O_3+NO_2+O_2\)(Lỗi tiếp)

6.\(3Fe_3O_4+8Al\rightarrow4Al_2O_3+9Fe\)

7.\(3Fe_xO_y+2yAl\rightarrow3xFe+yAl_2O_3\)

nuyen4011

a, Hiện tượng: Khi cho quỳ tím vào dd NaOH, quỳ tím chuyển xanh. Sau khi dẫn khí SO₃ đến dư vào dd trên, quỳ tím chuyển đỏ.

b, Hiện tượng: Khi sục khí CO₂ đến dư vào nước vôi trong, xuất hiện kết tủa rồi kết tủa bị hòa tan.

PT: \(CO_2+Ca\left(OH\right)_2\rightarrow CaCO_{3\downarrow}+H_2O\)

\(CaCO_3+CO_2+H_2O\rightarrow Ca\left(HCO_3\right)_2\)

Bạn tham khảo nhé!

Vì B gồm 17 nguyên tử => x + 5y = 17 (1)

Mà: PTK_X = 342

=> 27x + (32+16.4)y = 342 (2)

Từ (1) và (2) => x = 2; y = 3

Vậy: CTHH của B là Al₂(SO₄)₃.

Bạn tham khảo nhé!

1. before / wash / eating! / your / Remember / hands / to

=> Remember to wash your hand before eating.

2. improve / skills. / to / Read / lot / a / writing / your

=> Read to improve your writing skills.

3. me / not / Richard / rush. / tells / to /.

=> Richard tells me not to rush.

4. before / Watch / it. / step / your / taking .

=> Watch it before taking step.

5. eat / cookies. / tells / sister / My / all / the / me / not / to

=> My sister tells me not to eat all the cookies.

6. room. / reminds / My / to / clean / mother / me / my .

=> My mother reminds me to clean my room.

7. pack / clothes! / Make / you / warm / sure

=> Make sure you pack warm clothes.

8. package / the / Leave / the / at / door.

=> Leave the package at the door.

9. door / the / Walk / and / to / through / left / to / turn / the / go / library.

=> Walk through the door and turn left to go to the library.

10. of / glass / me / a/ pour / tells / her / water. / to / Liz

=> Liz tells me to pour her a glass of water.

1. before / wash / eating! / your / Remember / hands / to

=> Remember to wash your hand before eating.

2. improve / skills. / to / Read / lot / a / writing / your

=> Read to improve your writing skills.

3. me / not / Richard / rush. / tells / to /.

=> Richard tells me not to rush.

4. before / Watch / it. / step / your / taking .

=> Watch it before taking step.

5. eat / cookies. / tells / sister / My / all / the / me / not / to

=> My sister tells me not to eat all the cookies.

6. room. / reminds / My / to / clean / mother / me / my .

=> My mother reminds me to clean my room.

7. pack / clothes! / Make / you / warm / sure

=> Make sure you pack warm clothes.

8. package / the / Leave / the / at / door.

=> Leave the package at the door.

9. door / the / Walk / and / to / through / left / to / turn / the / go / library.

=> Walk through the door and turn left to go to the library.

10. of / glass / me / a/ pour / tells / her / water. / to / Liz

=> Liz tells me to pour her a glass of water.

nuyen4011

C24: D

C25: C

C26: B

C27: D

C28: C

C29: C

Bạn tham khảo nhé!

Câu 1:

Ta có: \(n_{Cu}=\frac{6,4}{64}=0,1\left(mol\right)\)

PT: \(2Cu+O_2\rightarrow2CuO\)

_____0,1_____________0,1 (mol)

\(\Rightarrow m_{CuO}=0,1.80=8\left(g\right)\)

\(\rightarrow\) Đáp án: C

Câu 2:

PT: \(2KClO_3\rightarrow2KCl+3O_2\)

_______0,2_________________0,3

\(\Rightarrow V_{O_2}=0,3.22,4=6,72\left(l\right)\)

\(\rightarrow\) Đáp án: D

Câu 3:

Ta có: \(n_{CuO}=\frac{16}{80}=0,2\left(mol\right)\)

\(n_{H_2}=\frac{6,72}{22,4}=0,3\left(mol\right)\)

PT: \(CuO+H_2\rightarrow Cu+H_2O\)

Xét tỉ lệ: \(\frac{0,2}{1}< \frac{0,3}{1}\) , ta được H₂ dư.

Theo PT: \(n_{Cu}=n_{CuO}=0,2\left(mol\right)\)

\(\Rightarrow m_{Cu}=0,2.64=12,8\left(g\right)\)

\(\rightarrow\)Đáp án: B

Bạn tham khảo nhé!

SO2 + Ca(OH)2 →Ca(HSO3)2

Ca(HSO3)2 có phải là kết tủa không?
Ko nha bn nó là dung dịch pha loãng thôi

 Ca(HSO3)2 có phải là kết tủa ko?

đáp án:

Ca(HSO3)2 ko phải kết tủa