Lối Sống's Vội Vàng's

2 năm trước

Quặng pirit sắt (FeS2) khí oxi hiđro và các chất cần thiết khác em hãy viết PTHH để điều chế được sắt nguyên chất

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Nhật Dương

2 năm trước

4FeS2 + 11O2 ->(t0) 2Fe2O3 + 8SO2

Fe2O3 + 3H2 ->(t0) 2Fe + 3H2O

Trang Luong Nguyen

2 năm trước

PTHH:

2FeS2+ 11/2O2→ Fe2O3+ 4SO2

Fe2O3+ 3H2→ 2Fe+ 3H2O

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Quặng pirit sắt (FeS2) khí oxi hiđro và các chất cần thiết khác em hãy viết PTHH để điều chế được sắt nguyên chất

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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Quặng pirit sắt (FeS2) khí oxi hiđro và các chất cần thiết khác em hãy viết PTHH để điều chế được sắt nguyên chất

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.