Since $G$ is a group, we have $G = HK = KH$. Splitting $G$ up into the (finite number of) right cosets $Kg$, we have: $G = Kg_1 \cup Kg_2 \cup\cdots \cup Kg_n$, for some finite number of $g_i$.

水解常数(Hydrolysis equilibrium constant)即水解平衡常数。水解常数是表示水解的程度的量，常用符号Kh表示。盐类在溶液中，与水作用而改变溶液的酸碱性的反应叫作盐类的水解。

2024年9月10日 · Learn how to maintain proper KH levels in your aquarium. Read our guide for tips on how to raise & lower KH in aquarium and ensuring a healthy tank environment!

Let $H$ and $K$ be subgroups of a group $G$. We know that $HK$ is a subgroup of $G$ if and only if $HK=KH$. Is it true that $HK$ is a subgroup of $G$ if and only if either $H$ or $K$ is a normal subgroup of $G$? Clearly if $H$ or $K$ is a normal subgroup of $G$, then $HK=KH$ which implies $HK$ is a subgroup of $G$.

KH is measured in dKH (degrees of KH) or ppm (parts per million), where 1 dKH equals 17.9 ppm. Typically, freshwater aquariums should be between 4-8 dKH (or 70-140 ppm). If you need to lower the pH for animals like discus or crystal shrimp, you’ll need to decrease the KH to 0 …

2018年3月8日 · Let $H$ and $K$ be subgroups of $G$. Prove that $HK$ is a subgroup of $G$ if and only if $HK=KH$. In particular, the condition holds if $hk=kh$ for all $h$ in $H$ and $k$ in $K$.

高中化学中，Ka、Kw、Kh分别表示以下概念： Ka：酸的离解常数，表示酸在溶液中离解产生H+离子的程度，Ka越大，酸越强。 Kw：水的离子积常数，表示水分子自离解平衡中水离子浓度的乘积，Kw = [H+][OH-]，在25°C时，Kw = 1.0 × 10^-14。

黄铁矿氧化产生的Fe^3+水解生成Fe (OH)3沉淀时，其水解常数kh=kw/ka (Fe^3+)=1×10^-14/6.3×10^-3≈1.6×10^-12，由此计算理论pH值可预测矿物表面反应进程，为生态修复方案提供数据支撑。 历史维度上，该关系式的建立与酸碱质子理论的发展密不可分。 1923年布朗斯特和劳莱提出质子理论后，科学家们逐步认识到水解反应本质是质子转移过程，由此将传统的水解常数与解离常数统一在质子理论框架下，这一理论突破使原先分散的化学现象获得了统一解释。 现代 …

2022年9月9日 · Aquarium KH levels, or rather alkalinity, control the water's ability to buffer acids that are constantly created by different reactions taking place inside an aquarium. Knowing the GH, KH, and pH levels of your tap water will help you …

2022年5月2日 · Carbonate hardness (kh) is one of the ways to check and judge water quality in aquariums, and it measures dissolved carbonate concentration and bicarbonates in fish tanks. The ideal kh helps to keep the water in the tank at stable parameters, and when it’s low, it can result in spikes of some other compounds in the aquarium, like gh.