相关实验视频
Updated: Jul 11, 2026

09:31
Calcium Carbonate Formation in the Presence of Biopolymeric Additives
Published on: May 14, 2019
概括
新开放的碳酸含有独特的双盐,二碳酸-碳酸. 这种不稳定的化合物在室温下在空气中迅速分解为二碳酸.
科学领域:
- 化学 化学 化学
- 晶体学 晶体学是指结晶学.
- 材料科学 材料科学 材料科学
背景情况:
- 商用试剂级"碳酸盐"广泛用于各种化学应用.
- 了解试剂的精确组成和稳定性对于可重复的科学结果至关重要.
研究的目的:
- 为了识别商业试剂级"氨碳酸盐"新开封容器中存在的晶体相.
- 描述这种独特的晶体相的化学和物理特性.
- 确定已识别的化合物的稳定性和分解途径.
主要方法:
- 化学成分分析 化学成分分析
- 测量光学常数的测量常数
- 在X射线粉末衍射 (XRPD) 过程中,
- 红外 (IR) 吸收光谱学
- 密度的确定 密度的确定
主要成果:
- 一个独特的晶体相被确定为唯一的成分.
- 分析表明该化合物是一种双盐:二碳酸-碳酸 (NH(4) HCO(3).NH(4) CO(2) NH(2)).
- 盐在环境温度下在空气中不稳定,迅速分解为二碳酸.
结论:
- 商用试剂级"氨碳酸"不是纯氨碳酸,而是双盐.
- 鉴定到的二碳酸-碳酸是不稳定的,很容易分解.
- 准确识别试剂成分对于化学应用至关重要.
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Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
Each alkylation step makes the nitrogen center more nucleophilic, which triggers successive alkylations until a quaternary ammonium salt is formed. Considering...
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Using the ICE table and substituting the Kb value, we calculate the initial pH of 50 mL of 0.1 M ammonia to be 11.11. Addition of 25 mL of 0.1 M hydrochloric acid to this solution of ammonia results in a buffer with an equal concentration of ammonia and ammonium ions. The pH of this buffer can be calculated by substituting these...
Using the ICE table and substituting the Kb value, we calculate the initial pH of 50 mL of 0.1 M ammonia to be 11.11. Addition of 25 mL of 0.1 M hydrochloric acid to this solution of ammonia results in a buffer with an equal concentration of ammonia and ammonium ions. The pH of this buffer can be calculated by substituting these...
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For instance, group IV...
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