Đốt cháy hết 13g KL(II) trong bình chứa khí CL2 dư thu đc 27,2g muối clorua. Xđ tên KL đc sử dụng?

By Trang Ánh Nam -
Đốt cháy hết 13g KL(II) trong bình chứa khí CL2 dư thu đc 27,2g muối clorua. Xđ tên KL đc sử dụng?

Giải:
2M    +        xCl2 -->2MClx    (x là số mol của kim loại)
…………0,2
Khối mượng Cl2 tham gia phản ứng là:
mCl2=27,2-13=14,2  ( bảo toàn khối lượng)
số mol Cl2 tham gia phản ứng:
n===0,2 mol.
Ta có: M==32,5x
ü Với x=1 thì M=32,5 không có nguyên tố thỏa yêu cầu.
ü Với x=2 thì M=65 kim loại là Zn
ü Với x=3 thì M=97,5 không có nguyên tố thỏa yêu cầu.
ü Với x=4 thì M=130 không có nguyên tố thỏa yêu cầu.
Vậy kim loại cần tìm là Zn.

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