CHEMISTRY COMMUNITY

Rita Dang 3D

It refers to the fact that the stronger the acid, the weaker its conjugate base, and the stronger the base, the weaker its conjugate acid.

Rita Dang 3D

Chromium regulates glucose metabolism. Iron facilitates oxygen transportation. Cobalt (Vitamin B12) prevents anemia and mental illness. Zinc is a master hormone that is critical for enzyme function.

Rita Dang 3D

If the reaction is exothermic, taking away heat will make the reaction favor the products. If the reaction is endothermic, taking away heat will make the reaction favor reactants.

Rita Dang 3D

To determine the number of binding sites, we look at the number of atoms that have extra lone pairs to donate, not the number of lone pairs one atom has. H2O is monodentate because the Oxygen atom is the only atom that have extra electron pairs. Oxalate is bidentate because it has two Oxygen atoms t...

Rita Dang 3D

Does anyone know if we need to look at the formal charges when determine whether the dipole moments cancel or not? I know we need to draw the lewis structure and consider the shape first. And then see if the partial charges cancel or not. But is formal charge related to partial charges and the conce...

Rita Dang 3D

Professor Lavelle just updated the solution manual errors.
It should be "x is the equilibrium partial pressure."

Rita Dang 3D

We use bis- and tris- instead of di- and tri- when the ligand is polydentate, such as EDTA (6 binding sites) and en (2 binding sites).

Rita Dang 3D

I think dipole moments depend on the electronegativity of each element and also the structure of the compound. By looking at the structure of a compound and determining its shape, we can decide whether the dipole moments cancel each other or not. In other words, we need to know the lewis structure a...

Rita Dang 3D

The key distinction between a sigma and a pi bond is that a sigma bond is formed by an end-by-end overlap while a pi bond is formed by a side-by-side overlap. Sigma bond is always the first bond formed between 2 atoms. All single covalent bonds are sigma bonds.

Rita Dang 3D

I think it would be linear if there are no lone pairs on the central atom

Rita Dang 3D

When we try to predict or determine bond angles, do we look at the electron distribution instead of the shape (or positions of atoms)?

Rita Dang 3D

It is basically saying that the number of covalent bonds depends on the valence of an atom. For instance, Carbon has 4 valence electrons, and therefore it can form 4 covalent bonds with other atoms. Hydrogen only has 1 valence electron, and therefore it can only form 1 covalent bond.

Rita Dang 3D

Remember when drawing Lewis Structures, we almost always have to satisfy the octet rule for Oxygen first because it has a high electronegativity.

Rita Dang 3D

Does negative electron affinity mean energy must be supplied to push an electron onto an atom?
If so, would more negative electron affinity mean lower electron affinity since it takes more energy for the atom to gain an electron?

Rita Dang 3D

Can anyone explain to me why Cl has a higher electron affinity than Br?

Rita Dang 3D

Carbon has a higher electron affinity than nitrogen because nitrogen is already in its half-filled stable state. Carbon is more likely to gain one more electron so it can reach a more stable state.

Rita Dang 3D

Since Phosphorus is a half-filled subshelled atom (already in its stable state), Sulfur has a greater electron affinity than Phosphorus right?

Rita Dang 3D

Just to make sure. 300 has only 1 sig fig. And 300. has 3 sig figs right?

Rita Dang 3D

Zinc only has two valence electrons. It has 30 electrons in its outer shell. Its electron configuration is [Ar]3d^10 4s^2. 4s is its outer most shell, which contains 2 electrons.

Rita Dang 3D

The equation the solutions manual uses is the same thing as ∆p∆x=h/4pi. The "h" the solution manual uses in the equation ∆p∆x= "h"/2 represents h/2pi, which is the same thing as h/4pi if you multiply it out.

Rita Dang 3D

The significance behind Heisenberg's uncertainty (indeterminacy) equation is that measurement process influence outcome at atomic level. The more we know about an electron's momentum the less we know about its position. So I think C is the correct answer.

Rita Dang 3D

^2 only applies to v, not the whole equation.

Rita Dang 3D

Since the question tells us that the line is observed in the ultraviolet spectrum of atomic hydrogen, we can infer the line being observed belong to the Lyman series (by the definition of Lyman series). In Lyman series, we always have n_1=1.

Rita Dang 3D

You always plug in 9.109x10^-31kg for m if you are calculating the kinetic energy of an electron.

Rita Dang 3D

For 29, convert kJ to J first and then divide the number by the number of atoms per mole.

Rita Dang 3D

These are my steps: hv-150600J.mol^-1=1.99x10^-19J
hv=150600J
v=2.27x10^38HZ
So I basically plugged numbers into the formula E(photon)-E(energy remove e-)=E_k(e-)

Rita Dang 3D

The question asks "in photoelectric experiments, typically what part of the electromagnetic spectrum is the incoming light?"

I know the answer is Ultraviolet. But why?

Rita Dang 3D

Light hits a sodium metal surface and the velocity of the ejected electron is 6.61 x 105 m.s-1. The work function for sodium is 150.6 kJ.mol-1. Answer the following three questions. A. What is the kinetic energy of the ejected electron? B. How much energy is required to remove an electron from one s...

Rita Dang 3D

When a question asks about the number of molecules, atoms, or formula units, is it asking for the same thing?

Rita Dang 3D

Side reactions and impurities can also cause differences between actual and theoretical yield.

Rita Dang 3D

The question tells us that the compound is made of carbon, hydrogen, oxygen, and nitrogen, and it asks us to find its empirical formula. I know how to figure out the moles of each element and the ratio between them. But how do you know which element goes first when you write the formula? Like does i...

CHEMISTRY COMMUNITY

Search found 31 matches

Re: Seesaw

Re: Biological Importance

Re: Le Chatelier's Principle

Re: 17.33 Homework

Dipole moments and Formal Charges

Re: HW 11.43

Re: di, bis, tri, tris, etc

Re: Dipole Moments

Re: Sigma and Pi Bonds

Re: Bent or linear?

Bond Angles

Re: Valence of an Atom [ENDORSED]

Re: HOCO [ENDORSED]

Negative Electron Affinity

Re: 2.67

Re: 2.67

Re: Electron Affinity [ENDORSED]

300 vs 300. [ENDORSED]

Re: D-block valence electrons? [ENDORSED]

Re: ch1 question 43

Re: Post Module Question #16

Re: Question about Ek

Re: 1.15 Homework Question

Re: Photoelectric Effect: Post Module Assessment Q. 28, 29, and 30

Re: Photoelectric Effect: Post Module Assessment Q. 28, 29, and 30

Re: Q31 from online assessment

Question from online assessment [ENDORSED]

Q31 from online assessment

#of molecules/atoms/formula units

Re: Theoretical and Percentage Yield

M21