Why is SiO2 higher melting point than SO2? Where SiO2 has strong covalent bonds between molecules, SO3 only has weak van der waals intermolecular forces holding its molecules together. Since covalent bonds require more energy to overcome than van der waals,SiO2 requires a higher temperature than ...
Why would SO2 go down in solubility when temperature increases? In recrystallization, why is it important to add the solvent to the solid, rather than the other way around? Why would ethanol be used to wash a precipitate after that precipitate had been washed with water?
科学技术的重大发明可以引领一个崭新的时代。第二次工业革命期间德国异军突起，主要得益于自然科学的研究成果。下列是德国科学家的成就有 ①奥斯特发现电流的磁效应②麦克斯韦建立系统的电磁学理论③赫兹证明了麦克斯韦理论④达尔文确立了进化论⑤伦琴发现“X射线” [ ]
What is the Lewis structure for the molecule O_3? What us formal charge and resonance? Based on electronegativity differences, would you expect the O-O bonds in ozone to be polar? It turns out that these bonds are polar; what could explain this?
Which atom is more electronegative? Explain why. A. Be B. Mg C. Cl D. C Which of the following is a dipole? a. KrF_2 b. NH_2Cl c. CH_2Br_2 d. SCN^- Which of these species has resonance forms? a. PH3 b. HCN c. CO d. CH3OH e. SO2 Which o...
将4名司机和8名售票员分配到四辆公共汽车上，每辆车上分别有1名司机和2名售票员，则可能的分配方案种数是 （ ）
thus upsetting the imbalance of the environment. What’s more, other harmful gases, such as methane, nitrous oxides (NOx), carbon monoxide (CO), sulphur dioxide (SO2) and others are also emitted into the air. Depending on their concentrations in the troposphere, they can negatively ...
Again they are in a flat layer. The difference between being in the layer and not in the layer is just a few feet. This layering of the air into wet and dry layers is not limited to clouds. Seemingly clear air also contains exactly the same kind of variation in layers. This was very...
Different compounds have different elements and structures, but these are not the only differences. Different compounds also have different melting points, polarities, and solubility. So compounds are different from each other to various extents when it comes to any chemical or ph...
In chemistry, we can define a solute as the substance, which is the dissolved part of any matter or solution. A solute is also a substance dissolved with the other substance is called the solvent.Answer and Explanation: Many reasons make water the best solute: Water is a polar molecule,...