関連する実験動画
Updated: Dec 9, 2025

11:00
Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
11.4K
多相バッファ理論は,大気中のエアロゾールの酸性の相違を説明する.
Guangjie Zheng1, Hang Su2, Siwen Wang3
1Minerva Research Group, Max Planck Institute for Chemistry, Mainz 55128, Germany.
まとめ
エアロゾールのpHは,人口密度が高い地域では,アンモニア/アンモニアによって大幅に緩衝されます. 化学組成だけでなく エアロゾルの水分と質量濃度が エアロゾルの pHと大気化学を理解する鍵です
科学分野:
- 大気化学
- 環境科学
- 地化学
背景:
- エアロゾールの酸性は,大気中の粒子化学と環境への影響に影響を与える重要な要因です.
- エアロゾルのpHの要因を理解することは,大気中の過程を予測するのに不可欠です.
- エアロゾルのpH調節におけるバッファリング剤の役割は,さらなる調査を必要とする.
研究 の 目的:
- エアロゾール中の個々の物質のバッファリング能力を調査する.
- 人口が多い大陸の主要バッファリングシステムを特定する.
- エアロゾールのpH変化を制御する要因を解明する.
主な方法:
- マルチフェーズバッファ理論の開発
- バッファリング剤との関係でエアロゾールのpHを分析する.
- エアロゾールの水分と質量濃度の影響の評価
主要な成果:
- アンモニア/アンモニア (NH4+/NH3) 結合酸塩ペアは,大陸の大気溶液における支配的なバッファリング剤である.
- エアロゾールのpH値は,存在しているバッファリング剤によって大きく変化します.
- アエロゾールの水分と質量濃度は,アンモニア・バッファリング地域における粒子の組成よりも影響力があります.
結論:
- マルチフェーズバッファ理論は,エアロゾールのpHの観測された変化を説明する.
- 人為的なアンモニアの排出は,エアロゾールのpHと大気中の多相化学に影響を及ぼします.
- 窒素循環に対する人類時代の影響は,大気中のエアロゾールの性質の重要な要因です.
関連する概念動画
Buffers
171.3K
A solution containing appreciable amounts of a weak conjugate acid-base pair is called a buffer solution, or a buffer. Buffer solutions resist a change in pH when small amounts of a strong acid or a strong base are added. A solution of acetic acid and sodium acetate is an example of a buffer that consists of a weak acid and its salt: CH3COOH (aq) + CH3COONa (aq). An example of a buffer that consists of a weak base and its salt is a solution of ammonia and ammonium chloride: NH3 (aq) + NH4Cl...
171.3K
Mixtures of Acids
982
The pH of a solution containing an acid can be determined using its acid dissociation constant and initial concentration. If a solution contains two different acids, then its pH can be determined using one of several methods depending on the relative strength of the acids and their dissociation constants.
In a strong and weak acid mixture, the strong acid dissociates completely and becomes a source of almost all the hydronium ions present in the solution. In contrast, the weak acid shows...
In a strong and weak acid mixture, the strong acid dissociates completely and becomes a source of almost all the hydronium ions present in the solution. In contrast, the weak acid shows...
982
Mixtures of Acids
21.2K
The pH of a solution containing an acid can be determined using its acid dissociation constant and its initial concentration. If a solution contains two different acids, then its pH can be determined using one of several methods depending upon the relative strength of the acids and their dissociation constants.
A Mixture of a Strong Acid and a Weak Acid
In a mixture of a strong acid and a weak acid, the strong acid dissociates completely and becomes a source of almost all the hydronium ions...
A Mixture of a Strong Acid and a Weak Acid
In a mixture of a strong acid and a weak acid, the strong acid dissociates completely and becomes a source of almost all the hydronium ions...
21.2K
Buffer Effectiveness
54.3K
Buffer solutions do not have an unlimited capacity to keep the pH relatively constant . Instead, the ability of a buffer solution to resist changes in pH relies on the presence of appreciable amounts of its conjugate weak acid-base pair. When enough strong acid or base is added to substantially lower the concentration of either member of the buffer pair, the buffering action within the solution is compromised.
The buffer capacity is the amount of acid or base that can be added to a given volume...
The buffer capacity is the amount of acid or base that can be added to a given volume...
54.3K
Buffers: Overview
8.4K
Buffers play a crucial role in stabilizing the pH of a solution by mitigating the effects of small amounts of added acid or base. They consist of a weak acid and its conjugate base or a weak base and its conjugate acid. A solution of acetic acid and sodium acetate is an example of a buffer that consists of a weak acid and its salt: CH3COOH (aq) + CH3COONa (aq). An example of a buffer that consists of a weak base and its salt is a solution of ammonia and ammonium chloride: NH3 (aq) + NH4Cl (aq).
8.4K
Titration of a Weak Base with a Strong Acid
7.2K
The titration curve of a weak base like ammonia with a strong acid like hydrochloric acid is the mirror image of the titration curve of a weak acid with a strong base.
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...
7.2K

