对羟基苯甲酸乙酯钠加氢氧化钠可长期保存?(1)防腐剂对羟基苯甲酸乙酯钠盐水解:NaO-C6H4-COOCH2CH3+ H2O ==== HO-C6H4-COOCH2CH3+ NaOH,添加氢氧化钠,平衡往左边走,NaO-C6H4-COOCH2CH3的NaO-不被空气氧化,
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/21 19:57:57
![对羟基苯甲酸乙酯钠加氢氧化钠可长期保存?(1)防腐剂对羟基苯甲酸乙酯钠盐水解:NaO-C6H4-COOCH2CH3+ H2O ==== HO-C6H4-COOCH2CH3+ NaOH,添加氢氧化钠,平衡往左边走,NaO-C6H4-COOCH2CH3的NaO-不被空气氧化,](/uploads/image/z/9834392-56-2.jpg?t=%E5%AF%B9%E7%BE%9F%E5%9F%BA%E8%8B%AF%E7%94%B2%E9%85%B8%E4%B9%99%E9%85%AF%E9%92%A0%E5%8A%A0%E6%B0%A2%E6%B0%A7%E5%8C%96%E9%92%A0%E5%8F%AF%E9%95%BF%E6%9C%9F%E4%BF%9D%E5%AD%98%3F%EF%BC%881%EF%BC%89%E9%98%B2%E8%85%90%E5%89%82%E5%AF%B9%E7%BE%9F%E5%9F%BA%E8%8B%AF%E7%94%B2%E9%85%B8%E4%B9%99%E9%85%AF%E9%92%A0%E7%9B%90%E6%B0%B4%E8%A7%A3%EF%BC%9ANaO-C6H4-COOCH2CH3%2B+H2O+%3D%3D%3D%3D+HO-C6H4-COOCH2CH3%2B+NaOH%2C%E6%B7%BB%E5%8A%A0%E6%B0%A2%E6%B0%A7%E5%8C%96%E9%92%A0%2C%E5%B9%B3%E8%A1%A1%E5%BE%80%E5%B7%A6%E8%BE%B9%E8%B5%B0%2CNaO-C6H4-COOCH2CH3%E7%9A%84NaO-%E4%B8%8D%E8%A2%AB%E7%A9%BA%E6%B0%94%E6%B0%A7%E5%8C%96%2C)
}H5T5Nf&13u*jl^ ZgpDapP@YMUrw_g("对羟基苯甲酸乙酯钠加氢氧化钠可长期保存?(1)防腐剂对羟基苯甲酸乙酯钠盐水解:NaO-C6H4-COOCH2CH3+ H2O ==== HO-C6H4-COOCH2CH3+ NaOH,添加氢氧化钠,平衡往左边走,NaO-C6H4-COOCH2CH3的NaO-不被空气氧化,
对羟基苯甲酸乙酯钠加氢氧化钠可长期保存?
(1)防腐剂对羟基苯甲酸乙酯钠盐水解:NaO-C6H4-COOCH2CH3+ H2O ==== HO-C6H4-COOCH2CH3+ NaOH,添加氢氧化钠,平衡往左边走,NaO-C6H4-COOCH2CH3的NaO-不被空气氧化,溶液可长期保持不被氧化.
(2)碱性条件下酯完全水解:HO-C6H4-COOCH2CH3 + H2O====HO-C6H4-COOH + CH3CH2OH,HO--C6H4-COOH的酚羟基易被空气氧化,杀菌力不能保持.
问:(1)对羟基苯甲酸乙酯钠溶液加氢氧化钠互相矛盾,溶液可长期保存吗?(2)改加酸NaO-C6H4-COOCH2CH3 + H2O==== HO-C6H4-COOCH2CH3+ NaOH,生成较多HO-C6H4-COOCH2CH3,HO-被空气氧化?对羟基苯甲酸乙酯钠加氢氧化钠可长期保存?(1)防腐剂对羟基苯甲酸乙酯钠盐水解:NaO-C6H4-COOCH2CH3+ H2O ==== HO-C6H4-COOCH2CH3+ NaOH,添加氢氧化钠,平衡往左边走,NaO-C6H4-COOCH2CH3的NaO-不被空气氧化,
这种情况其实你可以加缓冲溶液,因为对羟基苯甲酸乙酯钠盐水解时的ph明显小于碱性水解的ph.
所以加少量的naoh的时候是可以长期保持的,如果加了大量的naoh则会水解生成盐(杀菌力可能不会减少,因为生成的是盐,没有酚羟基存在).
反正就是保持在一定的ph上,才能满足保存的要求.