ductai1932005

2 năm trước

Bột sắt có lẫn bột nhôm. Nêu 3 phương pháp làm sạch bột sắt

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Quang Cường

2 năm trước

Hỗn hợp Fe, Al:

C1: Cho hỗn hợp vào dd NaOH dư. Al tan, Fe ko tan lọc ra

Al+ NaOH+ H2O -> NaAlO2+ 3/2H2

C2: Đưa nam châm mạnh gần hỗn hợp để hút hết bột sắt ra.

C3: Cho hỗn hợp vào dd FeCl2 dư, để một thời gian đến khi phản ứng xảy ra hoàn toàn. Chất rắn spu là Fe đc lọc ra

2Al+ 3FeCl2 -> 2AlCl3+ 3Fe

thanhthanh040983

2 năm trước

PP1 :cho nam cham

PP2: cho dung dich NAOH

PTHH:2 AL+2 H2O+2 NAOH--->2 NAALO2+3 H2

to ko bit pp3 nhe thong cam!!

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Bột sắt có lẫn bột nhôm. Nêu 3 phương pháp làm sạch bột sắt

2 câu trả lời

if you don't wear a helmet , you can't ride your bike => Unless

Choose the best answer.
I think you should buy ___ pack of mineral water instead. And you can also buy _ snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ____ cookies and soft candies.

Choose the best answer.
We should decorate our living room with _ orange banner. We also need ____ ribbons, balloons, party hats and costume.

Choose the best answer.
I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.

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Bột sắt có lẫn bột nhôm. Nêu 3 phương pháp làm sạch bột sắt

2 câu trả lời

if you don't wear a helmet , you can't ride your bike => Unless

Choose the best answer.I think you should buy _____ pack of mineral water instead. And you can also buy _____ snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ______ cookies and soft candies.

Choose the best answer.We should decorate our living room with _____ orange banner. We also need ________ ribbons, balloons, party hats and costume.

Choose the best answer.I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.

Đề thi - đề kiểm tra Xem thêm

Choose the best answer.
I think you should buy ___ pack of mineral water instead. And you can also buy _ snacks such as potato crisps, 3 kilos of mandarins, 2 kilos of apples, 3 bunches of bananas, ____ cookies and soft candies.

Choose the best answer.
We should decorate our living room with _ orange banner. We also need ____ ribbons, balloons, party hats and costume.

Choose the best answer.
I think that ______ cauliflower is not enough for 3 people. Let’s buy one more.