V
vvh193


cau 17 o bai tap tu luyen cua cau tao nguyen tu
e tim ra la FeCl3 nhung da la AlCl3
e k biet minh sai o dau ca
mong thay va cac ban chi giup
2p +n +3(2p' +n')=196 (1)
3(2p' + n') + 1=2p +n -1 +16 (2)
tu (2)\Rightarrow 6p' +3n'=2p+n+14
thay vao (1) \Rightarrow 4p+2n=182
\Leftrightarrow2p+n=91
ap dung ct \Rightarrow25.8\leqp\leq30,3
dua them vao dap an \Rightarrowp=26\RightarrowFe
e tim ra la FeCl3 nhung da la AlCl3
e k biet minh sai o dau ca
mong thay va cac ban chi giup
2p +n +3(2p' +n')=196 (1)
3(2p' + n') + 1=2p +n -1 +16 (2)
tu (2)\Rightarrow 6p' +3n'=2p+n+14
thay vao (1) \Rightarrow 4p+2n=182
\Leftrightarrow2p+n=91
ap dung ct \Rightarrow25.8\leqp\leq30,3
dua them vao dap an \Rightarrowp=26\RightarrowFe