em lam ngo ngo nhu ri cac chi xem co dung ko nha 80% la sai em doan rua???
goi kl do la A==>Aco hoa tri 1 : muoi tao thanh co the la A2CO3;AHCO3 hay la ca 2muoi
goi x la so mol cua muoi AHCO3==> so mol mmuoiA2CO3 la (0.6-x):2 thu dk co the la 1 or 2==>0<=x<or=0,03
de ko pạ xet truong hop = 0,3 thi ta co the xet rieng th chi co muoiA2CO3 em xet roi ko co gia tri A nao thoa man ca .roi ta xet th x=0 cung ko co th nao tm.ta xet bang cach gia su voi th hop x+0,3 nha: thi ta coM(A2CO3)=4,42:0,03==>.... ko co A tm
tt või=0
==>ta thu dk hh2muoi==> ta co:4,42:0.06<M(trung binh)<4,42;0,03
<=>98<M(tb)<147,3 ta lai xet tung th voiM=98==>2A+60<98<A+71==>19<A<27 ta chon dk:A<27
tt ta xet voi M=147,3 ta suy ra dk:43,5<A<76 ta chon dk A<76
tu do ta suy ra A la K em nghi la lam nhu rua nhung ko chac ti mo luon!!!!!