CHEMISTRY COMMUNITY

Rhea Palsule

When naming a cyclohexane with the substituents of Iodine and Bromine for example, would you give the lower number to the Bromine because of alphabetizing or would you give it to the Iodine because it has a higher atomic number?

Rhea Palsule

Do you determine which element substituent is prioritized to get the equatorial position in a chair conformation based on higher atomic number or higher atomic radius? For example with Br and Cl as substituents.

Rhea Palsule

What are the bond angles of the carbons in alkenes? For example C3H6?

Rhea Palsule

When drawing the arrow from nucleophiles to electrophile, what is an example of when only one electron moves from nucleophile to electrophile? It seems like all the examples are normally with double headed arrows.

Rhea Palsule

What is the difference between a spontaneous reaction and an energetically favorable reaction in terms of the graph of the reactants to products?

Rhea Palsule

In the problem, the volume is expanding from 3.3L to 9.2*10^5 L. However, when calculating the heat capacity for step 2, the solution says that volume is constant and C= 3/2(R). Shouldn't it be 5/2(R) because the pressure is constant?

Rhea Palsule

If you are given two half reactions (both written as reductions) and are asked to write the overall reaction, how do you determine which half reaction is the oxidized reaction and should be flipped? For example, 7A in the 2011 Midterm.

Rhea Palsule

Why is a system that is expanding freely considered to be doing zero work?

Rhea Palsule

When a system is isothermal, isn't q (enthalpy) always 0 because delta T is 0? In our practice quizzes, it showed q to equal -w. Is this because it was reversible? If it was irreversible, would q then be equal to 0?

Rhea Palsule

In homework problem 8.53, the answer key uses the equation q= -C x T. Why is moles or grams not taken into account for this problem? Why is it necessary to use this equation rather than q= n x C x T?

Rhea Palsule

When calculating enthalpy, how do you know when to use grams in the equation (grams x specific heat x change in temperature) or moles in the equation (moles x molar heat capacity x change in temperature) ? How do the two equations differ?

Rhea Palsule

When steam touches the skin, Dr. Lavelle explained how first it would phase change to water (40.7 kJ/mol) and then would decrease in temperature, still in the liquid phase. Could you predict how much the temperature of the water will actually decrease by taking the average of the temperature of the ...

Rhea Palsule

In the course reader, the definition of an autoprotolysis reaction is when one molecule transfers a proton to another molecule of the same type. What does it mean when it says "same type"? Does this mean an acid/base with its conjugate?

Rhea Palsule

For a compound with COO- attached, one of the O's has three lone pairs and therefore has a high affinity for protons and can pull off a hydrogen from water so that the formal charge becomes zero. However, once this occurs, the oxygen in water molecule has three lone pairs. Does this mean that the pr...

Rhea Palsule

When determining if a molecule is monodentate or polydentate, do you simply look at the number of lone electron pairs? Or should you also take formal charge into account? For example oxygen with 2 lone pairs and 2 bonds has a formal charge of 0 but 2 lone pairs. Does that mean it is polydentate or m...

Rhea Palsule

During lecture, Dr. Lavelle mentioned that a quick way to determine if a reaction follows a forward or reverse reaction by decreasing volume could be comparing the number of moles of both product(s) and reactant(s). How would you apply this if the moles were equal for both products and reactants? Wo...

Rhea Palsule

Is an anion such as PO4 3- , which has 3 single bonds and 1 double bond, considered polar? Would the double bond of one of the oxygens cause that oxygen to pull more electrons because it has a shorter distance from the central atom, causing a dipole moment?

Rhea Palsule

If the shape of a molecule is linear with lone pairs, is the bond angle always still 180 degrees or can it be less than that as a result of lone pair repulsion?

Rhea Palsule

Dr. Lavelle mentioned that when creating a Lewis diagram, lone pairs must be placed as far as possible from each other. However, with the Lewis structure of IF3, for example, the two sets of lone pairs for Iodine are right next to each other as the molecule forms a T-shape structure. Why aren't the ...

Rhea Palsule

During lecture, Dr. Lavelle mentioned that the 2nd ionization energy of an element is always higher. What about an element like magnesium when you have already removed an electron and the electron configuration is now [Ne]3s1? Wouldn't the element be more "willing" to give up another elect...

Rhea Palsule

In the course reader, it explains that angular momentum can have the values l=0,1,2,...,n-1. Since n can go all the way to 7, can the angular momentum go beyond 3? If so, what orbital does the angular momentum correspond to once it exceeds 3 with the f-orbital?

Rhea Palsule

During lecture, Dr. Lavelle mentioned that an increase in light intensity does not mean an increase in energy, but rather just an increase in number of photons emitted. However, by increasing the number of photons, which are packets of energy, isn't energy also increased as a result? Therefore, is i...

CHEMISTRY COMMUNITY

Search found 22 matches

Atomic number vs Alphabetizing

Equatorial Priority

Bond Angle of Alkene

Single Headed Arrow

Spontaneous Rxn vs Energetically Favorable

Winter 2015 Midterm 4B

Determining Overall Reaction

Expanding Freely

Isothermal

Calculating q (Enthalpy)

Enthalpy Calculation

Steam

Autoprotolysis

Protonating the Carboxyl Group

Dentates

Effects of Changing Volume

Polarity of Double Bonds

Linear Molecular Geometry

Lone Pair Repulsion for T-shape

2nd Ionization Energy

Angular Momentum

Increasing Intensity of Light