|
|
|
giai thich thi nghiem sau: lay 1 cay nho con nguyen bo re. nhung bo re da rua sach vao dd xanh metilen. mot luc sau, lay cay ra, rua sach bo re va lai nhung tiep vao dd CaCl2.quan sat dd CaCl2, chung ta se thay dd u khong mau chuyen dan sang mau xanh , tai sao vay?
|