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溴標(biao)準溶液各(ge)濃度各(ge)規格的產品(pin)齊全 實驗小技巧(qiao)：每次滴(di)(di)(di)定(ding)(ding)時，溶液的初讀數好從(cong)“0”開始，如(ru)果滴(di)(di)(di)定(ding)(ding)消耗溶液量很(hen)少，初讀數也可從(cong)下(xia)一(yi)個整數開始，如(ru)10.00mL、20.00mL等(deng)。如(ru)果滴(di)(di)(di)定(ding)(ding)半滴(di)(di)(di)溶液，可用(yong)洗(xi)瓶(ping)吹洗(xi)下(xia)去(qu)或(huo)將滴(di)(di)(di)定(ding)(ding)管輕輕靠一(yi)下(xia)錐瓶(ping)內壁(bi)，還(huan)可用(yong)玻璃棒引下(xia)去(qu)。滴(di)(di)(di)定(ding)(ding)應在光線(xian)充(chong)足的房間(jian)進行，滴(di)(di)(di)定(ding)(ding)臺上(shang)好放(fang)白色(se)瓷(ci)磚襯托。所有產品(pin)僅供(gong)科研(yan)使用(yong)，不得用(yong)于食用(yong)，醫療等(deng)其它用(yong)途。

硫(liu)氰酸鉀標(biao)準溶液 各濃度各規格的產品齊全 實驗小技巧：酸式(shi)滴定管下端的玻璃活塞，洗凈(jing)以后取出用(yong)濾紙將(jiang)其擦干，滌(di)上(shang)一層凡(fan)士林，（注意不要將(jiang)小孔堵塞）再套(tao)上(shang)橡(xiang)皮(pi)筋。此時，玻璃活塞應旋轉靈(ling)活自(zi)如。堿式(shi)滴定管下端的玻璃珠(zhu)應大小適度，便用(yong)操作。所有產品僅供科研使(shi)用(yong)，不得用(yong)于食用(yong)，醫療(liao)等其它(ta)用(yong)途(tu)。

氯化鋅標(biao)準溶液(ye) 各濃度各規格的(de)產品齊全 實驗小技巧(qiao)：滴定操作如果在(zai)三(san)角(jiao)瓶(ping)中進(jin)行(xing)，則左手(shou)操縱滴定管活塞，右(you)(you)手(shou)的(de)姆指與食(shi)指中指拿住三(san)角(jiao)瓶(ping)的(de)上(shang)端，整個握(wo)瓶(ping)的(de)手(shou)應向上(shang)抬(tai)，不(bu)(bu)使三(san)角(jiao)瓶(ping)被(bei)手(shou)遮住，影響(xiang)觀察。如果滴定在(zai)燒(shao)(shao)杯中進(jin)行(xing)，則右(you)(you)手(shou)持(chi)玻璃棒，玻璃棒應高出燒(shao)(shao)杯1/3或3-5cm。所有產品僅供(gong)科研使用(yong)，不(bu)(bu)得用(yong)于食(shi)用(yong)，醫療等其它用(yong)途。

硫(liu)氰酸銨標準溶液(ye) 各濃度(du)各規格的(de)產品(pin)齊全 實(shi)驗(yan)小(xiao)技巧：滴定(ding)(ding)速(su)度(du)以(yi)(yi)每秒3—5滴定(ding)(ding)為宜(yi)，滴定(ding)(ding)至終(zhong)點后，應(ying)(ying)等30秒鐘(zhong)以(yi)(yi)上(shang)再(zai)讀(du)(du)(du)(du)數(shu)。讀(du)(du)(du)(du)數(shu)時一種(zhong)(zhong)是(shi)(shi)夾在滴定(ding)(ding)架(jia)上(shang)讀(du)(du)(du)(du)數(shu)，使(shi)用(yong)(yong)這種(zhong)(zhong)方(fang)法讀(du)(du)(du)(du)數(shu)，滴定(ding)(ding)管(guan)在滴定(ding)(ding)架(jia)上(shang)應(ying)(ying)處(chu)于垂直狀態（從正面(mian)和側(ce)面(mian)兩面(mian)觀(guan)察滴定(ding)(ding)管(guan)都(dou)應(ying)(ying)垂直）。另一種(zhong)(zhong)是(shi)(shi)手(shou)拿(na)滴定(ding)(ding)管(guan)讀(du)(du)(du)(du)數(shu)，使(shi)用(yong)(yong)這種(zhong)(zhong)方(fang)法讀(du)(du)(du)(du)數(shu)，應(ying)(ying)手(shou)持滴定(ding)(ding)管(guan)的(de)上(shang)端，使(shi)其垂直。讀(du)(du)(du)(du)數(shu)時視線應(ying)(ying)與液(ye)面(mian)水平(ping)，先(xian)看大(da)刻(ke)度(du)，再(zai)讀(du)(du)(du)(du)分刻(ke)度(du)，好(hao)反(fan)復讀(du)(du)(du)(du)2次，做好(hao)原始記(ji)錄。所有產品(pin)僅供(gong)科(ke)研使(shi)用(yong)(yong)，不得用(yong)(yong)于食用(yong)(yong)，醫(yi)療等其它(ta)用(yong)(yong)途。

*標(biao)準(zhun)溶(rong)液 各(ge)濃(nong)度各(ge)規格的產(chan)(chan)品(pin)齊全 實驗小技巧：滴(di)(di)定(ding)時滴(di)(di)定(ding)管(guan)要(yao)伸入(ru)瓶(ping)(ping)（杯(bei)）口1/3—1/4或1cm左右(you)，左手要(yao)控(kong)制滴(di)(di)定(ding)速度，右(you)手要(yao)不(bu)斷均勻搖(yao)動(dong)錐(zhui)瓶(ping)(ping)，使溶(rong)液充(chong)分(fen)反(fan)應(ying)。搖(yao)動(dong)時不(bu)能(neng)(neng)碰撞滴(di)(di)定(ding)管(guan)，錐(zhui)瓶(ping)(ping)上端(duan)（即(ji)手持部(bu)位）不(bu)能(neng)(neng)偏(pian)離中(zhong)心軸（滴(di)(di)定(ding)管(guan)），只能(neng)(neng)使錐(zhui)瓶(ping)(ping)下端(duan)（底部(bu)）搖(yao)動(dong)，一般按順時針(zhen)方向搖(yao)動(dong)。如用(yong)燒(shao)杯(bei)滴(di)(di)定(ding)，滴(di)(di)定(ding)管(guan)伸入(ru)杯(bei)中(zhong)應(ying)離燒(shao)杯(bei)壁1—2cm，右(you)手持玻璃棒充(chong)分(fen)攪動(dong)，玻璃棒不(bu)能(neng)(neng)碰撞杯(bei)壁。所有(you)產(chan)(chan)品(pin)僅(jin)供科研(yan)使用(yong)，不(bu)得用(yong)于(yu)食用(yong)，醫(yi)療等其它用(yong)途。