Bai1 De trung hoa m gam hon hop X gom hai axit no don chuc mach ho ke tiep nhau trong day dong dang can 100ml dung dich NaOH 0,3M .Mat khac dem dot chay m gam hon hop X roi cho san pham [r]
(1)Bai1 De trung hoa m gam hon hop X gom hai axit no don chuc mach ho ke tiep day dong dang can 100ml dung dich NaOH 0,3M Mat khac dem dot chay m gam hon hop X roi cho san pham chay lan luot di qua binh dung P2O5 binh dung KOH du thay khoi luong binh tang a gam binh tang (3,64+a) gam.Thanh phan phan tram khoi luong axit co so nguyen tu cacbon nho hon hop X la A.30,14% B.33,33% C.69,68% D.66,67% Bai2 Dot hoan toan hon hop X gom nhung luong bang ve so mol cua FeS2 va Cu2S thu duoc 3,36 lit SO2 (dktc) va chat ran Y gom FeS2 va Cu2O hap thu het SO2 thu duoc bang dd nuoc Br2 vua du thu duoc dd Z co nong loang cho toan bo Y vao Z sau cac pu say hoan toan thi so gam chat ran lai khong tan la A.1.6gam B.3,2gam C.11,2gam D.14,4gam Bai3Cho hon hop X gom Fe va Cu vao 400ml dd chua hon hop gom H2SO4 0,5M va NaNO3 0,2M sau cac pu xay hoan toan thu duoc dd Y va NO (sp khu nhat) dong thoi kim loai chua tan Cho Vml ddNaOH vao dd X thi luong ket tua la lon nhat Gia tri toi thieu cua Vml la A.360 B.280 C.240 D.320 Bai4Mach RLC noi tiep gom cuon day(L r) va tu dien C Dat vao hai dau doan mach mot hieu dien the u=căn2cos(100pi t).Dieu chinh C dr Uc=Ucmax=50V.Hieu dien the hieu dung giua dau cuon day la A.30 B.40 C.50 D.80 Em dang on de chuan bi thi thu em mong anh co gang giai giup em voi Em xin cam on truoc nhe! (2)