Search found 21 matches

by Nisha Patel 3I
Mon Mar 07, 2016 9:21 pm
Forum: *Alkenes
Topic: Heat Capacity of Ethene
Replies: 1
Views: 343

Re: Heat Capacity of Ethene

Ethane is a single bond so it has more freedom to move. Ethene is a double bond so it is more rigid, which makes movement more difficult. More rotational modes, or more freedom to move, means it has a higher heat capacity. Ethane is also more complex than ethene because it has 2 more hydrogen atoms,...
by Nisha Patel 3I
Wed Mar 02, 2016 11:01 am
Forum: *Alkanes
Topic: Tert and sec groups chemical formula?
Replies: 1
Views: 381

Re: Tert and sec groups chemical formula?

The tert example given in the course reader was a butyl group, so it is C(CH 3 ) 3 . Sec is when the central carbon is attached to the second carbon in the chain. So for example, sec-butyl would be CH 3 CH 2 CH 2 CH 3 which the second carbon attached to the methyl group coming off of the longest cha...
by Nisha Patel 3I
Thu Feb 25, 2016 2:48 pm
Forum: *Free Energy of Activation vs Activation Energy
Topic: Whether a reaction will occur at room temperature
Replies: 2
Views: 2091

Re: Whether a reaction will occur at room temperature

A reaction will occur at room temperature if is activation energy is less than 80kJ/mol. In general, the activation energies tend to range from 40 to 150 kJ/mol.
by Nisha Patel 3I
Mon Feb 15, 2016 9:29 am
Forum: Reaction Mechanisms, Reaction Profiles
Topic: Course Reader page 75
Replies: 2
Views: 466

Re: Course Reader page 75

At equilibrium, the rates of the forward and reverse reactions are equal. Because of this, the equilibrium constant for a reaction is equal to the ratio of the rate constants for the forward and reverse reactions that contribute to the overall reaction. You can see how this is derived on page 781 in...
by Nisha Patel 3I
Tue Feb 09, 2016 1:01 am
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Electrodes in Cell Diagrams
Replies: 1
Views: 268

Re: Electrodes in Cell Diagrams

You put Pt(s) in the cell diagram in general if all of the substances in the half-reaction are aqueous. The anode/cathode should be a solid (I think there might be 1 or 2 cases where the anode/cathode is a liquid). If there is no solid in the reaction, Pt(s) is used as the anode/cathode. For example...
by Nisha Patel 3I
Tue Feb 02, 2016 2:30 pm
Forum: Balancing Redox Reactions
Topic: Redox Reactions
Replies: 1
Views: 254

Re: Redox Reactions

A redox reaction is basically a reaction that involves a transfer of electrons between 2 substances. The substance that gains electrons is reduced, and the substance that provides or loses its electrons is oxidized. The oxidation number of the substances are changed when they are reduced or oxidized...
by Nisha Patel 3I
Thu Jan 28, 2016 4:08 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Bond Enthalpies
Replies: 4
Views: 1051

Re: Bond Enthalpies

Yes, the bonds that are broken will be in the reactants, and the bonds that are formed will be in the products. Drawing the Lewis structures of each reactant and product will help you see which bonds are broken and which bonds are formed. For example, in homework problem #8.73b, the following reacti...
by Nisha Patel 3I
Tue Jan 19, 2016 10:40 am
Forum: Concepts & Calculations Using Second Law of Thermodynamics
Topic: HW 9.1 Rate of entropy of generation
Replies: 1
Views: 688

HW 9.1 Rate of entropy of generation

#9.1: "A human body generates heat at the rate of about 100. W (1 W  1 Js1). (a) At what rate does your body heat generate entropy in your surroundings, taken to be at 20. C?" In the solutions manual, they derived the following equation: Rate of entropy generation = \Delta Ssurr/time =...
by Nisha Patel 3I
Tue Jan 12, 2016 2:05 pm
Forum: Calculating Work of Expansion
Topic: Reversible and irreversible process
Replies: 2
Views: 397

Re: Reversible and irreversible process

A reversible process is when a very small change reverses the direction of the system. The change in internal energy is 0 in a reversible isothermal expansion. In an irreversible process, the direction of the system does not change. Usually in a problem, they will tell you if a process is reversible.
by Nisha Patel 3I
Fri Jan 08, 2016 3:21 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Characteristics that give higher heat capacities?
Replies: 3
Views: 1142

Re: Characteristics that give higher heat capacities?

To give you an example of a characteristic related to higher heat capacity, you can look at #8.29. The question asks which molecule, NO or NO 2 , has the higher molar heat capacity. The answer is NO 2 because it is the more complex molecule. Complex molecules tend to have higher heat capacities beca...
by Nisha Patel 3I
Fri Dec 04, 2015 8:27 pm
Forum: Properties & Structures of Inorganic & Organic Bases
Topic: Acid Strength
Replies: 1
Views: 793

Acid Strength

In this problem, how do you know that H has more electron withdrawing ability than CH 3 ? Fall 2013 Final Exam: #Q7B "List the following acids in order of increasing strength and explain why: CF 3 COOH (1), CH 3 COOH (2), CCl 3 COOH (3), C(CH 3 ) 3 COOH (4)" Answer: 4<2<3<1 Electron withdr...
by Nisha Patel 3I
Fri Nov 27, 2015 12:14 am
Forum: Bronsted Acids & Bases
Topic: Determining Acids and Bases
Replies: 5
Views: 730

Re: Determining Acids and Bases

You can also tell if an acid/base is strong by looking at its ionization in water. If it is nearly or completely ionized, you know it is strong. If only a few molecules are ionized, you know the acid/base is weak.
by Nisha Patel 3I
Sat Nov 21, 2015 8:48 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: how will equilibrium shift
Replies: 3
Views: 424

Re: how will equilibrium shift

You can also think of this in terms of pressure. Volume and pressure have an inverse relationship according to the PV=nRT equation, so if volume is increased, then pressure is decreased. A decrease in pressure favors the side with more moles of gas, so the equilibrium will shift in the direction whe...
by Nisha Patel 3I
Tue Nov 10, 2015 8:51 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Naming
Replies: 2
Views: 461

Re: Naming

When you are given the name of a coordination compound, how do you know what order to write the ligands in when you are writing the coordination compound's chemical formula? Do you just write the ligands in the alphabetical order that they are given in?
by Nisha Patel 3I
Thu Nov 05, 2015 9:08 pm
Forum: Lewis Structures
Topic: Lewis Structure of HClO3
Replies: 3
Views: 16033

Lewis Structure of HClO3

When drawing the Lewis structure of HClO3, how do you know that the H atom is bonded to the O instead of to the central Cl atom?

Image
by Nisha Patel 3I
Sat Oct 31, 2015 12:41 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Full MO Energy Diagram
Replies: 1
Views: 190

Full MO Energy Diagram

If we are asked for the full molecular energy diagram of a diatomic molecule, would we just have to include the 1s orbital? In diatomic molecules that don't include hydrogen, would we ever have to include the 1s orbital in our MO energy diagram?
by Nisha Patel 3I
Fri Oct 30, 2015 3:42 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Lone Pair Repulsion in Bent Molecules
Replies: 5
Views: 1088

Re: Lone Pair Repulsion in Bent Molecules

[/img] http://www.chemthes.com/icon_2/3508.gif Hi! In the case of AX2E3, it is considered linear. If you look at how the lone pairs are shown in the image, you can see in what directions the lone pairs are pulling. Because of this lone pair arrangement, a linear shape is formed. Overall since it's l...
by Nisha Patel 3I
Sat Oct 24, 2015 12:53 am
Forum: Resonance Structures
Topic: Resonance
Replies: 2
Views: 515

Re: Resonance

For example, look at O3. There are 3 O atoms. The central O atom has a double bond with 1 of the O atoms, and it has a single bond with the other O atom. You know this structure has resonance because you can switch which atom has the double bond and which has the single bond without there being any ...
by Nisha Patel 3I
Sat Oct 17, 2015 3:18 pm
Forum: Lewis Structures
Topic: Drawing & Determining Correct Lewis Structure
Replies: 4
Views: 606

Re: Drawing & Determining Correct Lewis Structure

Looking at the (SO4)2- example given in class, the Lewis structure that had atoms with formal charges of 0 was more stable than the Lewis structure in which the formal charge of the sulfur/oxygen atoms was > or < 0. I think if you check the formal charge of the structures, you should be able to dete...
by Nisha Patel 3I
Fri Oct 09, 2015 6:55 pm
Forum: Heisenberg Indeterminacy (Uncertainty) Equation
Topic: Heisenberg Equation Purpose
Replies: 2
Views: 470

Re: Heisenberg Equation Purpose

I think the purpose of the equation is mostly to estimate the movement of a particle. Because particles are constantly moving, its hard to specify where exactly they are location-wise, so the Heisenberg Equation tries to locate a particle based on delta x, where x is the uncertainty of the particle'...
by Nisha Patel 3I
Sat Oct 03, 2015 12:14 pm
Forum: *Shrodinger Equation
Topic: Shrodinger Equation
Replies: 1
Views: 405

Shrodinger Equation

For what kinds of problems will we use this equation? What does the equation signify?

Go to advanced search