Question

某煉爐廠日產(chǎn)生鐵（含雜質(zhì)的質(zhì)量分?jǐn)?shù)為4%）2240t，計(jì)算需含F(xiàn)e₂O₃質(zhì)量分?jǐn)?shù)為80%的赤鐵礦質(zhì)量．

Answer 1

【答案】分析：利用變化前后鐵元素質(zhì)量相等解決，計(jì)算時(shí)先要把不純的物質(zhì)轉(zhuǎn)化為純凈物計(jì)算，一般是物質(zhì)的質(zhì)量乘以這種物質(zhì)中純凈物的質(zhì)量分?jǐn)?shù)就使混合物轉(zhuǎn)化成了純凈物的質(zhì)量．
解答：解：生鐵中鐵的質(zhì)量是：m（Fe）=2240t×（1-4%）=2150.4t
Fe₂O₃中鐵的質(zhì)量分?jǐn)?shù)為：=0.7；
需要的Fe₂O₃的質(zhì)量==3072t
則需要需含F(xiàn)e₂O₃質(zhì)量分?jǐn)?shù)為80%的赤鐵礦質(zhì)量是：3072t÷80%=3840t
答：需含F(xiàn)e₂O₃質(zhì)量分?jǐn)?shù)為80%的赤鐵礦質(zhì)量是3840t．
點(diǎn)評(píng)：此題是對(duì)含雜質(zhì)物質(zhì)的有關(guān)化學(xué)計(jì)算，問(wèn)題的關(guān)鍵是首先解決純凈物與混合物的相互轉(zhuǎn)化，混合物的質(zhì)量乘以某種物質(zhì)的質(zhì)量分?jǐn)?shù)即為這種純凈物質(zhì)的質(zhì)量，再利用化學(xué)式是解決這類(lèi)題目的關(guān)鍵．