Đáp án: Đốt cháy hoàn toàn 19,2 gam kim loại R trong không khí Sau phản ứng cần dung vừa đủ 400 ml dung dịch axit clohiđric 1,5M để hòa tan hết oxit Tìm R - Đáp án Cu Giải thích các bước giải 4R+nO2->2R2On R2On+2nHCl->2RCln+nH2O nHCl=0,4x1,5=0,6(mol) =>nR2On=0,6/2n=0,3/n(mol) =>nR=0,3/nx2=0,6/n(mol) MR=19,20,6/n=32n n=2 thì MR=64 => R là Cu(đồng)

Tùng Vũ Thanh

2 năm trước

Đốt cháy hoàn toàn 19,2 gam kim loại R trong không khí. Sau phản ứng cần dung vừa đủ 400 ml dung dịch axit clohiđric 1,5M để hòa tan hết oxit. Tìm R

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Nhật Dương

2 năm trước

Đáp án:

Giải thích các bước giải:

4R+nO2->2R2On

R2On+2nHCl->2RCln+nH2O

nHCl=0,4x1,5=0,6(mol)

=>nR2On=0,6/2n=0,3/n(mol)

=>nR=0,3/nx2=0,6/n(mol)

MR=19,2:0,6/n=32n

n=2 thì MR=64

=> R là Cu(đồng)

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Đốt cháy hoàn toàn 19,2 gam kim loại R trong không khí. Sau phản ứng cần dung vừa đủ 400 ml dung dịch axit clohiđric 1,5M để hòa tan hết oxit. Tìm R

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Choose the best answer.
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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.
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Đốt cháy hoàn toàn 19,2 gam kim loại R trong không khí. Sau phản ứng cần dung vừa đủ 400 ml dung dịch axit clohiđric 1,5M để hòa tan hết oxit. Tìm R

1 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.

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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.

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