CHEMISTRY COMMUNITY

Abraham De Luna

Catherine Bubser 2C wrote:Is the oxidizing agent the molecule that has been reduced?

Yes it is.

Abraham De Luna

Scot Widjaja Dis 1J wrote:Hey guys. Can someone explain to me how to balance this redox reaction? How are we meant to balance the hydrogens in the reaction?

You should try balancing each half reaction first so that it is easier to do.

Abraham De Luna

Hello, I am a bit lost on balancing redox reactions as I have looked at some explanations and I have seen the use of adding electrons in order to balance the equation and I was a bit lost and was wondering if someone could explain how these added electrons will later be canceled out in order to rec...

Abraham De Luna

I am having a hard time figuring out this problem. This is the problem I have: Write a balanced overall reaction from these unbalanced half-reactions. In--->In^3+ Cd^2+--->Cd The guidance it gives me is: First, balance the charge of the half‑reactions by adding electrons. Electrons should always be...

Abraham De Luna

We do not have to memorize them but there are some that you should try to remember.

Abraham De Luna

We are supposed to use Hfus when we are trying to calculate a phase change from a solid to liquid.

Abraham De Luna

when the substance is going through a phase change it is not at equilibrium.

Abraham De Luna

I believe that it could be used for both.

Abraham De Luna

STP would mean that the temperature is at 0 degrees celsius.

Abraham De Luna

The main difference is the Cv value is when the volume is constant whereas the Cp value is when the pressure is constant.

Abraham De Luna

I think that it might be referring to the Gibbs free energy equation which is delta G= Delta H - T(DeltaS)

Abraham De Luna

Yes we usually assume that the system is closed unless we are told otherwise.

Abraham De Luna

K is just a unit for temperature.

Abraham De Luna

One example of when work is being done on a system would be the example that we were given in class where a piston is compressing the gas.

Abraham De Luna

The way I think of it is that in an isolated system both heat and matter can not exchange with the surrounding system.

Abraham De Luna

The difference is that molar heat capacity is the amount of energy required to a mole by a degree celcius or kelvin whereas the enthalpy is known as the total energy of a system.

Abraham De Luna

The negative sign is represented when the work is being done by the system.

Abraham De Luna

You have to take the units you are using into consideration when deciding which r constant to use.

Abraham De Luna

Typically the organic chemistry tutor is a lot of help with topics that you might need help with.

Abraham De Luna

A closed system would not allow for an exchange in matter because it is a fixed amount.

Abraham De Luna

The Cp and Cv for liquids and solids will remain the same.

Abraham De Luna

I believe if it is on both sides then we can proceed to cancel them out.

Abraham De Luna

Hess' Law states that the enthalpy of the overall reaction is equivalent to the sum of the smaller enthalpies in the reaction.

Abraham De Luna

A phase change is when there is a change of state of matter.

Abraham De Luna

Q is used to denote heat and H is used to denote enthalpy.

Abraham De Luna

In order to go from a liquid to a gas we must use heat to increase the enthalpy.

Abraham De Luna

Endothermic reactions will always have a positive delta H whereas an exothermic reaction will always have a negative delta H.

Abraham De Luna

The change in reactants is always negative while the change in products is always positive.

Abraham De Luna

Yes, temperature is the only thing that can change the value of K.

Abraham De Luna

You can calculate the total pressure by simply adding all of the partial pressure values.

Abraham De Luna

It is probably recommended that you just remember what the strong and weak acids are.

Abraham De Luna

Yes, the reactants will always be on the left and the products will always be on the right.

Abraham De Luna

When you are using the quadratic formula you can ignore the negative answer that you get back.

Abraham De Luna

Typically, all single bonds have one sigma bond and all double bonds have one sigma bond and one pi bond. Also, a triple bond would have a one sigma bond and two pi bonds. So when you are counting the amount of sigma bonds in a molecule make sure to consider the sigma bonds present in double and tri...

Abraham De Luna

You should consider the electronegativity between the atoms in the molecule and whether the dipole moments created counteract each other or not.

Abraham De Luna

For this question make sure you take into consideration all the possible types of bonds that could used. You should also consider the arrangement you put the molecules in. Also make sure if there are any rings that you can form. Good Luck!

Abraham De Luna

An example of a non-polar molecule would O2 and it is non-polar because there are not any partial charges present.

Abraham De Luna

From my understanding, the negative poles would be found towards the atom that is more electronegative.

Abraham De Luna

Yes, I believe that it can help determine polarity because because VSPER helps determine the shape and structure of the molecule.

Abraham De Luna

For Midterm 2 we should expect to see any material after MT1 to the end of outline 3.

Abraham De Luna

The bond angle will depend on the arrangement of electrons and molecular shape.

Abraham De Luna

I think it is safe to assume that we will have to know how to recognize the shapes and angles.

Abraham De Luna

There are not any hydrogen bonds because H is not bonded to anything that has a high electronegativity.

Abraham De Luna

yeah it seems like the length of the bacterium would be the same wavelengths of the photon.

Abraham De Luna

After finding the wavelength then you can use c= wavelength x frequency to find the frequency. All you would have to do is manipulate the formula and plug in what you have.

Abraham De Luna

(velocity)= h/(mass)(wavelength)

Abraham De Luna

Yeah, I believe you are supposed to use that as the wavelength.

Abraham De Luna

I dont think you need to worry about that since the questions on the midterm will be multiple choice.

Abraham De Luna

Thanks guys, these explanations were very helpful.

Abraham De Luna

Normally you would want to wait until the final answer before you round.

Abraham De Luna

Unless the questions states otherwise, I would go ahead and use the finals unit that you would end up with.

Abraham De Luna

It seems like kelvin is the main one that we will be using in class but I would still be familiar with the other ones just in case.

Abraham De Luna

I believe that we do not have to worry about remembering most conversion factors and that they will be given to us.

Abraham De Luna

It is to emphasize that the oxygen is what is bonded and not the hydrogen.

Abraham De Luna

The roman numeral is the charge of the metal in the compound.

Abraham De Luna

The oxidation number refers to the charge the molecule has.

Abraham De Luna

I think the coordination number is the number of bonds attached to the central ion.

Abraham De Luna

yes that is what it is.

Abraham De Luna

You should list them in alphabetical order based on the root.

Abraham De Luna

Cis molecules would be polar and trans molecules are nonpolar.

Abraham De Luna

You must put them in alphabetical order and then consider the charge.

Abraham De Luna

An amphiprotic is a something that can both accept and donate a proton.

Abraham De Luna

Acids will usually have h atoms.

Abraham De Luna

One of the differences is that bronsted acids donate protons, however Lewis acids accept electrons.

Abraham De Luna

Water molecules use both Hydrogen atoms to form a hydrogen bond.

Abraham De Luna

A single bond would have 1 sigma bond, a double bond would have a sigma bond and a pi bond, and a triple bond would have a sigma bond and 2 bonds.

Abraham De Luna

The way that it works is that a single bond would have a sigma bond. A double bond would have a sigma bong and pi bond and a triple bond would have a sigma bond and two pi bonds.

Abraham De Luna

Noble gases have no electronegativity sincecthey already have a full octet

Abraham De Luna

Yes since the molecule with the lone pair would alter the degrees of the bond angles.

Abraham De Luna

The presence of hydrogen bonds increases the melting point.

Abraham De Luna

As the electronegativity increases the atomic radius decreases.

Abraham De Luna

I recommend doing the homework on the chemical bonds section.

Abraham De Luna

Yes covalent bonds can only be formed by two non-metals.

Abraham De Luna

You choose the central atom by picking the atom that has the lowest ionization energy.

Abraham De Luna

Ionization energy is indeed the energy required to remove an electron from an atom.

Abraham De Luna

I believe that you find the atomic radius by measuring the distance between the nuclei of two touching atoms.

Abraham De Luna

Yes, it is a constant so it will always be the same.

Abraham De Luna

We would use the equation in order to find the energy of a photon. However, it does have other uses.

Abraham De Luna

Hz is equivalent to 1 cycle/second.

Abraham De Luna

Avogadro's number represents the number of atoms in per mol of a substance.

Abraham De Luna

Most of the time the limiting reactant is given in the problem, but it can either be in moles or grams it just depends on the circumstance.

Abraham De Luna

The law of conservation of mass states that atoms cannot be created or destroyed.

Abraham De Luna

He specified to do either fundamentals or quantum world for homework 2.

Abraham De Luna

Should I take sig figs while I am calculating one problem step by step? Should I use sig figs every step or should I just consider the sig figs on the very last calculation? I believe that you should only use significant figures on the last calculation. It is also important to keep in mind that sig...

Search found 84 matches