... mHBr pu = 0,03.2.81 = 4,86 (g) mHBr d = 5,26 4,86 = 0,4(g) 0, C%HBr d = 62,5 100 = 0, 64% Bi 11: Trn 11, 2 g bt Fe v g bt S chộn s em nung khụng cú khụng khớ phn ng xy to FeS vi hiu sut 80% Ly ... pH=13,5 (mụi trng baz mnh) d NaOH CNaOH [OH-]= 10-14/10-13,5 =0,028.P- 9,0.10-3 P = 11, 6 Vy nng % ca dung dch NaOH l 11, 6% Bi 8: Tớnh s gam NaOH phi cho vo hn hp thu c thờm 8,00 ml HNO3 0,0100 vo ... ban u thu c dung dch HCl cú pH = Bi 11: 8, H Dc 1998, Cho dung dch NaOH cú pH = 12 (dung dch A) Cn pha loóng bao nhiờu ln thu c dung dch NaOH cú pH = 11 Bi 12: H Kinh T Quc Dõn 1999 Pha loóng...