CHEMISTRY COMMUNITY

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Each hydrogen that is attached to either N, O, or F counts as a potential binding site and every lone pair on a N, O, or F atom

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pH=-log[H3O+]

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pH is a measure of hydrogen ion concentration while pOH is a measure of hydroxide ion concentration.

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if you are given the concentration of hydronium ions in a solution then pH= -log[H3O+]. If you are given the concentration of hydroxide ions then pH=-log[OH-]

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Lewis acids would actually have more protons than lewis bases since the definition for a lewis acid is that it accepts electron pairs while lewis bases donate electron pairs

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Chlorine has a larger atomic radius than Fluorine which makes it easier for chlorine to lose its hydrogen atom making it a stronger acid than fluorine.

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the strength of an acid is indicated by its Ka. The higher the Ka, the more it dissociates which means that it is a stronger acid

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Oxidation numbers indicate the number of electrons gained or lost by an atom in a molecule

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Besides memorizing the list of strong acids, they are also usually associated with longer and weaker bonds which indicates that it gives up hydrogen atoms easier.

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Equilibrium arrows are used in reactions in which weak acids and bases are involved since they do not dissociate completely.

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Acids usually contain hydrogen since acids are defined as substances that donate hydrogen ions.

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Valence bond theory basically states how atoms bond together through the combination of half filled orbitals to form hybrid orbitals which then create sigma and pi bonds.

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Electrons randomly distribute around a nucleus continuously. By that logic there are moments when there are more electrons concentrated in one area than another which creates a slightly uneven charge distribution which will cause a momentary dipole at one instantaneous second.

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No because pi bonds are formed in the presence of p orbitals and p orbitals are always preceded by s orbitals which create sigma bonds

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You just need to know that triple bonds consist of one sigma bond and two pi bonds

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Hydrogen bonds are weaker than ionic and covalent bonds mainly because hydrogen bonds are an intermolecular force while ionic and covalent bonds are an intramolecular force which are generally way stronger than intermolecular forces.

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When you look at the electron configurations for nitrogen and oxygen you can see that oxygen has one group of paired electrons. Due to the electron electron repulsions that occur as a result of the paired electrons, it is pushed to a higher energy level which causes it to require less energy to remo...

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All molecules have london dispersion forces due to the randomized dispersion of electrons at a singular moment which can strengthen the dipole towards a certain direction due an increased density of electrons.

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Ionic is stronger than covalent bonds since they have a greater attraction towards each other due to the opposite charges that ionic bonds possess that covalent bonds don't

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Polar bonds are stronger than nonpolar bonds. Coordinate covalent bonds are generally weaker than ionic/covalent bonds.

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Hydrogen bonds only form between N, O, and F due to its high electronegativity. The high electronegativity results in an increased negative charge in those atoms which heavily attracts H atoms in adjacent molecules.

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alpha represents the polarizability of the atom which correlates with the amount of electrons that are present in the molecule. This is because more electrons allow for more distribution around the molecule which can create stronger momentary dipoles between other molecules. r represents the distanc...

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Usually when a bond is shorter it is stronger, because there are more electrons that are shared between ions which result in a stronger pull between the electrons and the atoms' nuclei. The same goes for why a longer bond is weaker.

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Also it is helpful to check the formal charge on the central ion as expanded octets usually contribute to decreasing the formal charge to 0.

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Electronegativity decreases as you move down a group and increases as you move across a period. It increases as you move across a period because the nuclear charge increases as you move right. It decreases as you move down a group because the electrons are increasingly experiencing weaker attraction...

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When ions form bonds they release energy. Lattice energy is basically the amount of energy that is released when ions form a compound.

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In terms of bond energy triple bonds have the largest bond energy while single bonds have the smallest bond energy. Lone pair electrons also repel other lone pair electrons on adjacent atoms which contributes to single bonds having weaker bonds.

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Basically atoms have different electronegativities and the difference in electronegativities between two atoms is what causes a bond to be polar. So yes, they are correlated but they aren't the same.

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A formal charge of 0 indicates that the molecule is at its most stable structure.

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The midterm will include everything including Friday's lecture besides the last slide that was shown.

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Whenever you remove the first electron, you create a cation. So technically, the nuclear charge is greater which is why the second ionization energy is always significantly larger than the first.

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My TA mentioned how you can use the noble gas configuration whenever you want. You arent required to use the fully written out notation unless inquired to.

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Unless they specifically ask you to show the arrangement of electrons in the orbital, you should use the "s2p6d10" notation.

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All electromagnetic radiation is light itself which is why they all travel at 3*10^8 m/s. The factors that distinguishes the types of EM waves are frequency and wavelength.

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a nodal plane is an area where the probability of finding electrons is zero. S orbitals are the only orbitals that have nodal planes considering how the orbital itself is spherical and doesn't intersect the nucleus in any way

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The 3d orbital should have more energy than 4s since the electrons in the 3d orbital experience heavy repulsion from electron interactions between the other electrons in the 3d and 3p orbitals. As a result, it requires less energy for electrons to occupy the 4s orbital.

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A nodal plane is an area where there is no chance of finding an electron. S orbitals do not have this because they are spherical and don't have any gaps that p,d, and f orbitals possess

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Considering how the Balmer series is associated with visible light and the Lyman series is associated with UV light, wavelengths in the Balmer series should range from around 400 nm to 740 nm while wavelengths in the Lyman series should range from 10 nm to 400 nm.

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One routine that helped me get through chem was to just do as many practice problems as possible and to review the problems that you weren't able to solve initially or struggled with.

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Do the positive and negative values relate to the arrows he draws in class? I'm confused as to how that relates to the spin state. The positive and negative values don't necessarily correlate to a certain direction such as "up" or "down" that most people refer to, it just convey...

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Basically electrons in the 3d orbital have a lot of repulsion because of the electrons that occupy the 3s and 3p orbitals. Considering how the 4s orbital is further away and experiences less repulsion, it requires less energy for electrons to occupy it than the 3d orbital.

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It is in the ultraviolet region because the gap between n=1 and n=2 has the greatest gap compared to the other energy which results in the greatest energy release which can be associated to the ultraviolet region.

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Electrons closer to the nucleus are more affected by the pull and thus require more energy to remove. The further the electrons are from the nucleus, the weaker the pull, which results in less energy required to remove electrons.

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Simply put, aluminum has 3 valence electrons while sodium only has 1. It takes more energy for aluminum to lose 3 electrons to complete its octet shell than it does for sodium to lose one electron.

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Basically electron affinity is the amount of energy that is released when an electron is added to an atom while electronegativity is an atom's ability to attract electrons

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Can someone clarify why the Rydberg equation is always negative? Because you're "losing" energy because it's being transferred somewhere else? The Rydberg equation is negative because it is comparing the energy difference between the two levels the electrons transitioned between. When an ...

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Can someone clarify why the Rydberg equation is always negative? Because you're "losing" energy because it's being transferred somewhere else? The Rydberg equation is negative because it is comparing the energy difference between the two levels the electrons transitioned between. When an ...

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Back in high school, I was told to always put your answer in the original units stated in the problem if not given a specific unit to use.

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Molecular weight is basically the mass of one molecule. Molar mass would be the mass of a mole of a molecule.

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How important is it to know all the rules for sig figs? I feel like I know some basics but not the more specific rules that pertain to addition/subtraction or multiplication/division? Back in high school, I know that sig figs account for a lot of points so I believe that it is important that you fo...

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One important thing to note is that when determining the number of sig figs to use in your final answer, you don't consider the amount of sig figs in constants such as Avogadro's number.

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My TA mentioned how partial credit is possible to earn so it would be best if you show your work for every problem. When it comes to balancing chemical equations, you can earn partial credit if you write down the oxidation numbers for each compound/element.

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