Một oxi có chứa 50% oxi phần còn lại là một nguyên tố khác. Tìm nguyên tố đó biết khối lượng mol của oxit là 64

2 câu trả lời

Đáp án:

`A` là `S`

Giải thích các bước giải:

 Gọi nguyên tố tạo nên oxit là `A`

`-> CTHH : A_xO_y`

Mặc khác oxi chiếm `50%` thành phần oxit nên `x/y=1/2=>x=1;y=2`

`=> CTHH : AO_2`

Mà $M_{Oxit}=64(g/mol)$

`=>M_A+M_O.2=64`

`<=>M_A=64-M_O.2`

`<=>M_A=32`

Vậy `A` là lưu huỳnh `S`

`#nam`

Gọi CTHH của oxit đó là `A_x O_y` `(x, y \in NN`*)

Ta có: `y = (50% . 64)/16 = 2`

Mà: `M_{A_x O_2} = x . M_A + 2 . 16 = x . M_A + 32 = 64` (g/mol)

`-> x . M_A = 32` 

+ Nếu `x = 1` thì `M_A = 32` (g/mol)

`-> A:S` (lưu huỳnh) (chọn)

Vậy nguyên tố cần tìm là `S`.

 

Câu hỏi trong lớp Xem thêm

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