配制：取乙二胺四醋酸二鈉19g，加新沸過的冷水使成1000mL，搖勻。

標(biāo)定：取于800℃灼燒至恒重的基準(zhǔn)氧化鋅0.12g，精密稱定，加稀鹽酸3mL使溶解，加水25mL，加0.025%甲基紅的乙醇溶液1滴，滴加氨試液至溶液顯微黃色，加水25mL與氨-氯化銨緩沖液（pH10.0）10mL，再加鉻黑T指示劑少量，用本液滴定至溶液由紫色變?yōu)榧兯{(lán)色，并將滴定結(jié)果用空白試驗(yàn)校正。每1mL乙二胺四醋酸二鈉滴定液（0.05mol/L）相當(dāng)于4.069mg的氧化鋅。根據(jù)本液的消耗量與氧化鋅的取用量，算出本液的濃度。

貯藏：置玻璃塞瓶中，避免與橡皮塞、橡皮管等接觸。

硫酸鋅、性能：無色晶體,小針狀或粒狀晶形粉末,無臭,在空氣中會風(fēng)化。溶液對石蕊呈酸性比重1.957(25/4℃),熔點(diǎn)100℃在280℃失去7H2O,溶于水及甘油,不溶于酒精,毒性底。

蘋果公司今天在紐約股市收盤后發(fā)布了2016財(cái)年第三財(cái)季的財(cái)報(bào)，營收和利潤不出意外的下滑，不過因?yàn)榭偁I收和每股收益超過了市場預(yù)期，蘋果股票在目前的盤后交易中上漲了7.21%，重回100美元以上。

質(zhì)量指標(biāo)SpecificationGB25579-2010FCC,1996含量w/% ZnSO4.H2OContentZnSO4.H2O99.0-100.598.0-100.5ZnSO4.7H2OZnSO4.7H2O99.0-108.799.0-108.7砷(As),mg/kg          ≤As0.0003——堿金屬和堿土金屬鹽w/%≤Alkali metal0.500.5酸度PH通過試驗(yàn)正常硒(Se),mg/kg          ≤Se0.0030.003汞(Hg),mg/kg         ≤Hg0.00010.0005鉛(Pb),mg/kg          ≤Pb0.00040.001鎘(Cd),mg/kg          ≤Cd0.00020.0005

1、ChemicalName: Zinc sulfate

2、Molecular Formula :ZnSO4.H2O, ZnSO4.7H2O

3、MolecularWeight:179.48(Monohydrate), 287.54(Heptahydrate)

4、CAS:7446-19-7（H2O）；7446-20-0 (7H2O)

5、Character:It iscolorless or white crystalline powder,odorlessness. Efflorescence in air. Acid hydrometer is 1.957(25/4℃) to litmus.Melting point is 100℃. It’s soluble in water and glycerol, insoluble in ethanol and light toxicity, lose crystal water in 280℃.

  6、Usage:It is used as food additives, animal feed, printing and dyeing, timber preservative.Used as analytical reagent.

  7、Packing:It is packed with polythene bag as the inner layer, and a compound plastic woven bag as the outer layer. The net weight of each bag is 25kg.

8、Storage and Transport:It should be stored in a dry and ventilative warehouse; kept away form water and moisture during transport; unloaded with care, so as to avoid damage to bags. Furthermore, it should be stored separately from poisonous substances.

鋅是許多酶系統(tǒng)

(

如碳酸酐酶、乙醇脫氫酶和堿性磷酸酶等

)

的組成部分，鋅

缺乏可導(dǎo)致酶功能異常。

口服硫酸鋅可糾正鋅缺乏，

恢復(fù)酶系統(tǒng)的功能。

鋅離子

能沉淀蛋白質(zhì)，外用有收斂防腐作用，且能幫助肉芽組織形成。