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溴標(biao)準溶(rong)(rong)液(ye)各濃度各規格的產品(pin)齊全 實(shi)驗小技巧：每次滴(di)(di)定時(shi)，溶(rong)(rong)液(ye)的初(chu)讀數(shu)好(hao)從(cong)“0”開始(shi)，如果滴(di)(di)定消耗溶(rong)(rong)液(ye)量很少，初(chu)讀數(shu)也可從(cong)下(xia)一(yi)個整數(shu)開始(shi)，如10.00mL、20.00mL等。如果滴(di)(di)定半滴(di)(di)溶(rong)(rong)液(ye)，可用洗瓶吹(chui)洗下(xia)去(qu)或將滴(di)(di)定管輕(qing)輕(qing)靠(kao)一(yi)下(xia)錐瓶內(nei)壁，還可用玻(bo)璃(li)棒引下(xia)去(qu)。滴(di)(di)定應在光線充(chong)足(zu)的房間進行，滴(di)(di)定臺上好(hao)放白色瓷磚襯托。所有產品(pin)僅供(gong)科(ke)研使用，不得用于(yu)食用，醫療等其它用途。

硫氰酸(suan)鉀標準溶液 各濃度各規(gui)格的(de)產(chan)(chan)品(pin)齊(qi)全 實(shi)驗小(xiao)(xiao)技(ji)巧：酸(suan)式滴(di)定(ding)管下端的(de)玻(bo)璃活(huo)塞(sai)，洗凈以后取(qu)出用濾紙將其擦干，滌上一層凡士(shi)林，（注意不(bu)要(yao)將小(xiao)(xiao)孔堵(du)塞(sai)）再套上橡皮筋。此(ci)時(shi)，玻(bo)璃活(huo)塞(sai)應旋轉靈活(huo)自如。堿式滴(di)定(ding)管下端的(de)玻(bo)璃珠應大(da)小(xiao)(xiao)適度，便用操作(zuo)。所有(you)產(chan)(chan)品(pin)僅供科研使用，不(bu)得用于食用，醫(yi)療等其它用途。

氯化鋅標準溶液 各濃度各規格的(de)產品齊全 實驗(yan)小技巧(qiao)：滴(di)定操作如果在三角瓶(ping)(ping)中(zhong)進(jin)行，則左手(shou)操縱滴(di)定管活(huo)塞(sai)，右(you)手(shou)的(de)姆(mu)指與(yu)食(shi)指中(zhong)指拿住三角瓶(ping)(ping)的(de)上端，整個握瓶(ping)(ping)的(de)手(shou)應(ying)向上抬，不使三角瓶(ping)(ping)被手(shou)遮住，影響觀察。如果滴(di)定在燒(shao)杯中(zhong)進(jin)行，則右(you)手(shou)持玻(bo)璃(li)棒(bang)，玻(bo)璃(li)棒(bang)應(ying)高出(chu)燒(shao)杯1/3或3-5cm。所(suo)有(you)產品僅供科研使用，不得用于食(shi)用，醫療(liao)等其它(ta)用途(tu)。

硫氰(qing)酸銨標準溶液 各濃度(du)各規格的產(chan)品(pin)齊(qi)全(quan) 實驗小(xiao)技巧：滴(di)(di)(di)定(ding)(ding)速度(du)以每秒(miao)(miao)3—5滴(di)(di)(di)定(ding)(ding)為宜，滴(di)(di)(di)定(ding)(ding)至(zhi)終點后，應(ying)(ying)等30秒(miao)(miao)鐘(zhong)以上(shang)(shang)再(zai)讀(du)(du)數(shu)。讀(du)(du)數(shu)時一(yi)種(zhong)是夾(jia)在滴(di)(di)(di)定(ding)(ding)架上(shang)(shang)讀(du)(du)數(shu)，使(shi)用這(zhe)種(zhong)方法讀(du)(du)數(shu)，滴(di)(di)(di)定(ding)(ding)管(guan)在滴(di)(di)(di)定(ding)(ding)架上(shang)(shang)應(ying)(ying)處于(yu)垂直狀(zhuang)態（從正(zheng)面(mian)和側面(mian)兩面(mian)觀察滴(di)(di)(di)定(ding)(ding)管(guan)都(dou)應(ying)(ying)垂直）。另(ling)一(yi)種(zhong)是手拿滴(di)(di)(di)定(ding)(ding)管(guan)讀(du)(du)數(shu)，使(shi)用這(zhe)種(zhong)方法讀(du)(du)數(shu)，應(ying)(ying)手持滴(di)(di)(di)定(ding)(ding)管(guan)的上(shang)(shang)端(duan)，使(shi)其垂直。讀(du)(du)數(shu)時視線應(ying)(ying)與液面(mian)水(shui)平(ping)，先看大刻(ke)度(du)，再(zai)讀(du)(du)分刻(ke)度(du)，好反復讀(du)(du)2次，做好原(yuan)始記錄。所有產(chan)品(pin)僅供科研使(shi)用，不得(de)用于(yu)食用，醫療等其它用途。

*標準溶液(ye)(ye) 各(ge)濃(nong)度(du)各(ge)規(gui)格的產(chan)品(pin)齊(qi)全 實驗小技巧(qiao)：滴(di)定(ding)(ding)時滴(di)定(ding)(ding)管(guan)要(yao)伸(shen)入(ru)瓶(ping)(ping)（杯(bei)）口1/3—1/4或1cm左(zuo)右(you)，左(zuo)手(shou)(shou)要(yao)控制滴(di)定(ding)(ding)速度(du)，右(you)手(shou)(shou)要(yao)不斷(duan)均(jun)勻搖(yao)動(dong)錐瓶(ping)(ping)，使(shi)溶液(ye)(ye)充(chong)分(fen)反應。搖(yao)動(dong)時不能(neng)碰撞滴(di)定(ding)(ding)管(guan)，錐瓶(ping)(ping)上端(duan)（即手(shou)(shou)持(chi)(chi)部位）不能(neng)偏離中心軸（滴(di)定(ding)(ding)管(guan)），只能(neng)使(shi)錐瓶(ping)(ping)下(xia)端(duan)（底部）搖(yao)動(dong)，一般按順(shun)時針方向搖(yao)動(dong)。如(ru)用(yong)(yong)(yong)燒(shao)杯(bei)滴(di)定(ding)(ding)，滴(di)定(ding)(ding)管(guan)伸(shen)入(ru)杯(bei)中應離燒(shao)杯(bei)壁1—2cm，右(you)手(shou)(shou)持(chi)(chi)玻璃棒充(chong)分(fen)攪(jiao)動(dong)，玻璃棒不能(neng)碰撞杯(bei)壁。所有產(chan)品(pin)僅供科研(yan)使(shi)用(yong)(yong)(yong)，不得(de)用(yong)(yong)(yong)于食(shi)用(yong)(yong)(yong)，醫療等(deng)其它用(yong)(yong)(yong)途。