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溴標(biao)準溶液各濃度各規格(ge)的產品(pin)齊全(quan) 實驗小技巧：每次(ci)滴(di)(di)(di)定時(shi)，溶液的初(chu)讀(du)數(shu)好從(cong)“0”開(kai)始，如(ru)果滴(di)(di)(di)定消耗溶液量很少，初(chu)讀(du)數(shu)也(ye)可從(cong)下(xia)一個(ge)整數(shu)開(kai)始，如(ru)10.00mL、20.00mL等。如(ru)果滴(di)(di)(di)定半滴(di)(di)(di)溶液，可用(yong)(yong)洗瓶吹洗下(xia)去或將(jiang)滴(di)(di)(di)定管輕輕靠(kao)一下(xia)錐瓶內壁，還可用(yong)(yong)玻(bo)璃棒引下(xia)去。滴(di)(di)(di)定應(ying)在光線(xian)充足的房間進行(xing)，滴(di)(di)(di)定臺上好放白色瓷磚襯托。所有產品(pin)僅供科(ke)研(yan)使用(yong)(yong)，不得(de)用(yong)(yong)于食用(yong)(yong)，醫(yi)療等其它用(yong)(yong)途。

硫氰酸(suan)鉀標準(zhun)溶液 各(ge)(ge)濃度各(ge)(ge)規(gui)格的(de)產品齊全 實驗小技巧：酸(suan)式滴(di)(di)定(ding)管下(xia)端的(de)玻璃活(huo)塞，洗凈以(yi)后取(qu)出(chu)用濾紙將(jiang)其擦干，滌上一層凡士林(lin)，（注意不要將(jiang)小孔(kong)堵塞）再套(tao)上橡皮筋。此時，玻璃活(huo)塞應旋轉(zhuan)靈活(huo)自如。堿式滴(di)(di)定(ding)管下(xia)端的(de)玻璃珠應大小適(shi)度，便用操作。所有產品僅供科研使用，不得用于食(shi)用，醫療等其它用途。

氯化鋅標準溶液 各濃度(du)各規(gui)格的產(chan)品齊全 實驗(yan)小技巧(qiao)：滴定(ding)操作如果在三(san)角(jiao)瓶(ping)中進行，則(ze)左手操縱滴定(ding)管活塞，右手的姆指與(yu)食指中指拿住(zhu)三(san)角(jiao)瓶(ping)的上(shang)端，整個握(wo)瓶(ping)的手應(ying)向上(shang)抬，不使(shi)三(san)角(jiao)瓶(ping)被手遮(zhe)住(zhu)，影響(xiang)觀(guan)察。如果滴定(ding)在燒杯中進行，則(ze)右手持玻璃棒(bang)，玻璃棒(bang)應(ying)高出燒杯1/3或3-5cm。所(suo)有產(chan)品僅供科(ke)研(yan)使(shi)用(yong)(yong)(yong)，不得用(yong)(yong)(yong)于食用(yong)(yong)(yong)，醫療等(deng)其它用(yong)(yong)(yong)途。

硫氰酸銨標準溶(rong)液 各濃度(du)各規格(ge)的(de)產品(pin)(pin)齊全 實(shi)驗小技(ji)巧：滴(di)定(ding)速(su)度(du)以每(mei)秒3—5滴(di)定(ding)為宜，滴(di)定(ding)至終(zhong)點(dian)后，應(ying)等30秒鐘以上再讀(du)(du)(du)數。讀(du)(du)(du)數時一(yi)種(zhong)是夾在滴(di)定(ding)架上讀(du)(du)(du)數，使(shi)用(yong)(yong)這種(zhong)方法讀(du)(du)(du)數，滴(di)定(ding)管(guan)在滴(di)定(ding)架上應(ying)處于垂(chui)直(zhi)狀(zhuang)態（從正面和(he)側面兩面觀察滴(di)定(ding)管(guan)都應(ying)垂(chui)直(zhi)）。另一(yi)種(zhong)是手(shou)(shou)拿滴(di)定(ding)管(guan)讀(du)(du)(du)數，使(shi)用(yong)(yong)這種(zhong)方法讀(du)(du)(du)數，應(ying)手(shou)(shou)持滴(di)定(ding)管(guan)的(de)上端(duan)，使(shi)其垂(chui)直(zhi)。讀(du)(du)(du)數時視線應(ying)與液面水平，先看大刻度(du)，再讀(du)(du)(du)分刻度(du)，好(hao)反復讀(du)(du)(du)2次，做好(hao)原始記錄。所有產品(pin)(pin)僅(jin)供科研使(shi)用(yong)(yong)，不得用(yong)(yong)于食用(yong)(yong)，醫(yi)療(liao)等其它(ta)用(yong)(yong)途。

*標(biao)準溶液(ye) 各濃度各規(gui)格的產品齊全(quan) 實驗(yan)小技巧：滴(di)(di)定時(shi)滴(di)(di)定管(guan)要(yao)伸(shen)(shen)入瓶（杯(bei)(bei)）口(kou)1/3—1/4或1cm左右，左手(shou)(shou)要(yao)控制滴(di)(di)定速(su)度，右手(shou)(shou)要(yao)不(bu)(bu)斷均勻搖(yao)動(dong)錐瓶，使(shi)溶液(ye)充分反應(ying)。搖(yao)動(dong)時(shi)不(bu)(bu)能碰撞滴(di)(di)定管(guan)，錐瓶上端（即手(shou)(shou)持部位(wei)）不(bu)(bu)能偏(pian)離(li)中心軸（滴(di)(di)定管(guan)），只能使(shi)錐瓶下端（底部）搖(yao)動(dong)，一般(ban)按順時(shi)針方向搖(yao)動(dong)。如(ru)用(yong)(yong)燒杯(bei)(bei)滴(di)(di)定，滴(di)(di)定管(guan)伸(shen)(shen)入杯(bei)(bei)中應(ying)離(li)燒杯(bei)(bei)壁1—2cm，右手(shou)(shou)持玻(bo)璃棒(bang)充分攪動(dong)，玻(bo)璃棒(bang)不(bu)(bu)能碰撞杯(bei)(bei)壁。所(suo)有產品僅供科研使(shi)用(yong)(yong)，不(bu)(bu)得用(yong)(yong)于食用(yong)(yong)，醫(yi)療(liao)等其它(ta)用(yong)(yong)途。