Search found 87 matches

by Zoya Mulji 1K
Sun Feb 23, 2020 9:44 pm
Forum: Gibbs Free Energy Concepts and Calculations
Topic: Gp=Gr
Replies: 2
Views: 14

Re: Gp=Gr

If the rates of reactions are the same, the free energies on both sides of the equation should be the same.
by Zoya Mulji 1K
Sun Feb 23, 2020 9:41 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Test 2
Replies: 13
Views: 37

Test 2

What topics/outlines is Test 2 going to be on?
by Zoya Mulji 1K
Sun Feb 23, 2020 9:40 pm
Forum: Appications of the Nernst Equation (e.g., Concentration Cells, Non-Standard Cell Potentials, Calculating Equilibrium Constants and pH)
Topic: Nernst
Replies: 7
Views: 25

Nernst

What do all of the variables in the Nernst equation mean?
by Zoya Mulji 1K
Sun Feb 23, 2020 9:39 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Diagrams
Replies: 2
Views: 25

Cell Diagrams

Can someone explain what each part of the galvanic/voltaic cell is and what function it serves (ex. salt bridge)?
by Zoya Mulji 1K
Sun Feb 23, 2020 9:24 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Cell Potentials
Replies: 2
Views: 10

Cell Potentials

Which method/ equation can we use without changing the signs of the cathode/anode?
by Zoya Mulji 1K
Thu Feb 20, 2020 12:14 pm
Forum: Galvanic/Voltaic Cells, Calculating Standard Cell Potentials, Cell Diagrams
Topic: Purpose of Salt Bridge
Replies: 12
Views: 33

Re: Purpose of Salt Bridge

Since e- move from left to right, eventually, the e- would build up on the right side and that would cause the battery to stop working/ make the e- stop moving. To avoid this, the salt bridge allows for the movement of ions so that e- don't build up on the right side.
by Zoya Mulji 1K
Sun Feb 16, 2020 9:44 pm
Forum: Biological Examples (*DNA Structural Transitions, etc.)
Topic: organic reactions, and environmental and biological examples
Replies: 4
Views: 22

Re: organic reactions, and environmental and biological examples

I think he talked about biological examples with glycolysis/ cellular respiration and energy production
by Zoya Mulji 1K
Sun Feb 16, 2020 9:43 pm
Forum: Administrative Questions and Class Announcements
Topic: HW7
Replies: 14
Views: 31

Re: HW7

usually you should choose from the outline that we left off on/ were recently on
by Zoya Mulji 1K
Thu Feb 13, 2020 9:30 pm
Forum: Phase Changes & Related Calculations
Topic: Relation to entropy?
Replies: 3
Views: 15

Re: Relation to entropy?

going from a liquid to a gas also has greater entropy increase than going from a solid to a liquid
by Zoya Mulji 1K
Thu Feb 13, 2020 8:24 pm
Forum: Calculating Work of Expansion
Topic: Last Question on the Midterm [ENDORSED]
Replies: 5
Views: 69

Re: Last Question on the Midterm [ENDORSED]

I think the last question was about finding entropy in both an irreverisble and reversible expansion. You approach both using the entropy formula (i believe it was the change in volume formula) but this will only give you the answer to deltaS. To find deltaSsurrounding and deltaStotal you had to kno...
by Zoya Mulji 1K
Tue Feb 11, 2020 9:20 pm
Forum: Administrative Questions and Class Announcements
Topic: Pizza Rolls REVIEW Session DOWNLOAD HERE
Replies: 66
Views: 2259

Re: Pizza Rolls REVIEW Session DOWNLOAD HERE

Can someone show me step by step on how to solve for number 10. I did not understand why q(ice)=q(water). CHEM MOD: q(ice) = -q(water) DO NOT forget the negative sign. The heat released from one material in a system is absorbed by the other material in the system. For #10, why do we have to convert...
by Zoya Mulji 1K
Sun Feb 09, 2020 10:53 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: reversible reactions
Replies: 4
Views: 18

Re: reversible reactions

i'm pretty sure it should always tell us reversible or irreversible to indicate which equation to use.
by Zoya Mulji 1K
Sun Feb 09, 2020 10:51 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: work on the system or by the system
Replies: 4
Views: 11

Re: work on the system or by the system

if you use deltaU=q+w then w is negative when work is done by the system and w is positive when work is done on the system (if you are taking the perspective of the system)
by Zoya Mulji 1K
Sun Feb 09, 2020 10:46 pm
Forum: Calculating Work of Expansion
Topic: integration
Replies: 2
Views: 8

integration

do we ever need to use the integral for calculating work of expansion or can we always use the equation w/o it?
by Zoya Mulji 1K
Sun Feb 09, 2020 10:44 pm
Forum: Calculating Work of Expansion
Topic: Isothermal
Replies: 17
Views: 71

Re: Isothermal

along with isothermal, i think we also need to isobaric (constant pressure) and isochoric (constant volume)
by Zoya Mulji 1K
Sun Feb 09, 2020 10:39 pm
Forum: Entropy Changes Due to Changes in Volume and Temperature
Topic: Gas v Liquids
Replies: 4
Views: 11

Re: Gas v Liquids

for the reasons above liquids also have higher entropy than solids so entropy increases from the solid state to liquid state to gaseous state.
by Zoya Mulji 1K
Thu Jan 30, 2020 6:36 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Hess's Law vs. Standard Enthalpies of Formation
Replies: 5
Views: 31

Re: Hess's Law vs. Standard Enthalpies of Formation

I'm pretty sure that we will be given the multiple rxns and their enthalpies for Hess's Law.
by Zoya Mulji 1K
Thu Jan 30, 2020 6:30 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Work of expansion equation
Replies: 4
Views: 18

Work of expansion equation

Why do we add a negative in the work of expansion at constant pressure equation?
by Zoya Mulji 1K
Thu Jan 30, 2020 6:28 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Changing the energies of systems
Replies: 2
Views: 11

Changing the energies of systems

Can someone review how you can change the energies of the three types of systems?
by Zoya Mulji 1K
Thu Jan 30, 2020 6:26 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Work done by expansion
Replies: 8
Views: 34

Work done by expansion

Did we go over the equation for work done by expansion when P is not constant? Is that the same work equation with the integral included?
by Zoya Mulji 1K
Thu Jan 30, 2020 6:24 pm
Forum: Heat Capacities, Calorimeters & Calorimetry Calculations
Topic: Value of q
Replies: 11
Views: 56

Value of q

In a perfect system, what would/ should the values of q be?
by Zoya Mulji 1K
Sun Jan 26, 2020 7:29 pm
Forum: Phase Changes & Related Calculations
Topic: State Property
Replies: 3
Views: 9

Re: State Property

enthalpy is a state property which is a property that is not dependent on the path taken to obtain that state. This means that state properties can be added or subtracted and this like work or heat are not state properties.
by Zoya Mulji 1K
Sun Jan 26, 2020 7:28 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Using Method 2
Replies: 2
Views: 17

Re: Using Method 2

i think the method you use just depends on the information you are given and since bond enthalpy values are usually something you can look up/ would be given, you could use this method if you are not given the information for Hess's Law.
by Zoya Mulji 1K
Sun Jan 26, 2020 7:24 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Enthalpy
Replies: 3
Views: 9

Re: Enthalpy

enthalpy is the study of heat released or absorbed in chemical reactions and physical changes --> the amount of heat released or absorbed at a constant pressure is called enthalpy
by Zoya Mulji 1K
Sun Jan 26, 2020 7:22 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Friday Lecture
Replies: 2
Views: 11

Re: Friday Lecture

The third method was just using the formula where you sum the standard enthalpy of formation of the products and subtract the sum of the standard enthalpy of formation of the reactants from that.
by Zoya Mulji 1K
Sun Jan 26, 2020 7:20 pm
Forum: Reaction Enthalpies (e.g., Using Hess’s Law, Bond Enthalpies, Standard Enthalpies of Formation)
Topic: Hess's Law
Replies: 9
Views: 32

Re: Hess's Law

Hess's Law shows you that enthalpy changes are additive because enthalpy change at each stage can be added to give total enthalpy change.
by Zoya Mulji 1K
Thu Jan 16, 2020 5:02 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Product Yield
Replies: 6
Views: 18

Product Yield

How would you change the yield of a product without adding more reactants?
by Zoya Mulji 1K
Thu Jan 16, 2020 4:54 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: ICE and quadratic formula
Replies: 11
Views: 31

ICE and quadratic formula

How do you do the calculations for the ICE table without using the quadratic formula?
by Zoya Mulji 1K
Thu Jan 16, 2020 4:53 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Acids and Bases
Replies: 2
Views: 11

Acids and Bases

How does the concentration change when the pH value changes by a certain value?
by Zoya Mulji 1K
Thu Jan 16, 2020 4:51 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Water in Equilibrium Constant Eq.
Replies: 3
Views: 12

Water in Equilibrium Constant Eq.

With acid and base equilibrium reactions, why do you not include water in the equilibrium constant equation?
by Zoya Mulji 1K
Thu Jan 16, 2020 4:48 pm
Forum: Applying Le Chatelier's Principle to Changes in Chemical & Physical Conditions
Topic: Endothermic and exothermic
Replies: 5
Views: 17

Re: Endothermic and exothermic

If the reaction gives off heat while forming the product, then the heating will favor reactant formation (because additional heat is used) and this is exothermic.
by Zoya Mulji 1K
Thu Jan 09, 2020 6:05 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Values of K
Replies: 3
Views: 18

Values of K

Can someone summarize what the different ranges and values of K mean for the reactants and products?
by Zoya Mulji 1K
Thu Jan 09, 2020 5:59 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Textbook 5H.1 Part 1
Replies: 4
Views: 22

Re: Textbook 5H.1 Part 1

you want to take the square root because you want to manipulate the K equation for part (B) and make it look like the K equation for the original given reaction.
by Zoya Mulji 1K
Thu Jan 09, 2020 5:58 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Homework Question 5H.1
Replies: 2
Views: 17

Re: Homework Question 5H.1

For (B) first write out the K for this equation. When you write it out, you can see that this K looks almost similar to the K of the original given reaction. The only difference is the power to which each product and reactant is raised. If you multiplied the powers from the original K times 1/2, you...
by Zoya Mulji 1K
Thu Jan 09, 2020 5:53 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: 5G.11
Replies: 4
Views: 20

Re: 5G.11

You only want to include the product and reactant that are in the gaseous or aqueous state. Since the other products and reactants are solids and liquids you don't use them in your calculation of Q.
by Zoya Mulji 1K
Thu Jan 09, 2020 5:52 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: K pressure units
Replies: 3
Views: 15

Re: K pressure units

If you are looking for Kp then he said to write the units as atm.
by Zoya Mulji 1K
Fri Dec 06, 2019 12:06 am
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: 6C. 19 f)
Replies: 1
Views: 12

Re: 6C. 19 f)

because C is more electronegative, it is better at pulling and the O-H bond is easier to break. since this conjugate base is weaker/easier to break, its acid is stronger.
by Zoya Mulji 1K
Fri Dec 06, 2019 12:05 am
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: 6C.17
Replies: 2
Views: 23

Re: 6C.17

a strong base will come from a weaker acid so draw the conjugate bases for the given and see which one is a weaker acid.
by Zoya Mulji 1K
Fri Dec 06, 2019 12:03 am
Forum: Hybridization
Topic: Determining Hybridization
Replies: 4
Views: 26

Re: Determining Hybridization

look at regions of electron density and create orbitals based on that number.
by Zoya Mulji 1K
Thu Dec 05, 2019 10:49 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Resonance and Acidity
Replies: 2
Views: 32

Re: Resonance and Acidity

When the conjugate base of an acid is more electronegative, it is better at pulling so the O-H bond is easier to break. This means the conjugate base is weak and it's acid is stronger.
by Zoya Mulji 1K
Thu Dec 05, 2019 10:46 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: Coordination #
Replies: 6
Views: 40

Re: Coordination #

coordination # is the # of ligand molecules attached to the transition metal ion.
by Zoya Mulji 1K
Sat Nov 30, 2019 7:51 pm
Forum: Properties & Structures of Inorganic & Organic Acids
Topic: Weak Acids & Bases
Replies: 6
Views: 38

Re: Weak Acids & Bases

Benzoic acid is also a weak acid and you can remember this because the COOH in benzoic acid is often found in biological molecules and organic acids tend to be weaker.
by Zoya Mulji 1K
Sat Nov 30, 2019 7:49 pm
Forum: Shape, Structure, Coordination Number, Ligands
Topic: drawing
Replies: 1
Views: 35

drawing

What steps do you go through to draw a coordination compound?
by Zoya Mulji 1K
Sat Nov 30, 2019 7:45 pm
Forum: Biological Examples
Topic: Chemotherapy
Replies: 6
Views: 44

Chemotherapy

What are some examples of coordination compounds used as chemotherapy drugs?
by Zoya Mulji 1K
Sat Nov 30, 2019 7:37 pm
Forum: Calculating pH or pOH for Strong & Weak Acids & Bases
Topic: strong or weak base?
Replies: 13
Views: 55

Re: strong or weak base?

A weak base will partially dissociate but a strong base fully dissociates to give ions in a solution. Weak bases also have pH from 7 to 10 and strong ones have pH 10 to 14.
by Zoya Mulji 1K
Sat Nov 30, 2019 7:35 pm
Forum: Naming
Topic: Coordination Compounds on the Final
Replies: 4
Views: 27

Re: Coordination Compounds on the Final

We only really learned how to name them so I would probably just focus on/study that.
by Zoya Mulji 1K
Tue Nov 19, 2019 8:42 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Boiling and Melting Points
Replies: 1
Views: 30

Boiling and Melting Points

Can someone explain how to go about checking which molecules have the highest boiling points in a series? What steps do I take/ things that I check to put the molecules in the correct order?
by Zoya Mulji 1K
Tue Nov 19, 2019 8:38 pm
Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
Topic: Hydrogen Bonding/Pi bonds
Replies: 11
Views: 94

Re: Hydrogen Bonding/Pi bonds

Intermolecular forces:
ionic bonding --> H-bonding --> dipole-dipole bonding --> induced dipole/London dispersion
by Zoya Mulji 1K
Tue Nov 19, 2019 8:36 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Hydrogen bonding
Replies: 3
Views: 27

Re: Hydrogen bonding

Since N, O, and F all have super high electronegativity and H has a low electronegativity, they can have have a dipole moment between the atoms. --> you need the H because it's low electronegativity corresponds to the N, O, and F's high electronegativity.
by Zoya Mulji 1K
Tue Nov 19, 2019 8:33 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Effect of lone pair on bond angles
Replies: 2
Views: 29

Re: Effect of lone pair on bond angles

Yes it's because the actual atom is bigger so it's going to slightly decrease the bond angles by making the other atoms be a little closer together.
by Zoya Mulji 1K
Fri Nov 15, 2019 5:22 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: VSEPR Formula Exceptions
Replies: 6
Views: 40

Re: VSEPR Formula Exceptions

We probably don't have to deal with *exceptions* but still have to consider the changes when lone pairs are added or when different bonding atoms are changed.
by Zoya Mulji 1K
Fri Nov 15, 2019 5:20 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: 2E problem #13b.
Replies: 3
Views: 32

Re: 2E problem #13b.

I believe sometimes the bond angles can be slightly influenced if one bonding atom is significantly bigger than the other three bonding atoms, but in this context I think we only need to demonstrate a change in bond angles with the presence of a lone pair.
by Zoya Mulji 1K
Fri Nov 15, 2019 5:17 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: How to tell polar or non polar from lewis structure?
Replies: 9
Views: 63

Re: How to tell polar or non polar from lewis structure?

If you have the lewis structure, you can draw your dipole arrows considering electronegativity and if the arrows don't balance out then the molecule will be polar.
by Zoya Mulji 1K
Fri Nov 15, 2019 5:13 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Molecular Shape v Electron Geometry
Replies: 4
Views: 30

Re: Molecular Shape v Electron Geometry

With the electron geometry, all you have to consider is the number of things attached to the central atoms (lone pairs, atoms) to determine what the shape/geometry would be. When determining the molecular shape, you build off of this and determine how many of the "attached things" are lone...
by Zoya Mulji 1K
Fri Nov 15, 2019 5:10 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Molecule Size and Melting Points
Replies: 6
Views: 35

Re: Molecule Size and Melting Points

Bigger molecules do have higher boiling points but the shape of the molecule also can influence boiling point. For example, molecules with the same molecular formula but different shapes (branched vs. linear) can have different BPs.
by Zoya Mulji 1K
Fri Nov 08, 2019 2:00 pm
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Distinguishing between the different intermolecular forces
Replies: 9
Views: 303

Re: Distinguishing between the different intermolecular forces

Hydrogen bonding is easy to see because it is present in molecules with N, O, F atoms. The N, O, or F atoms have to have lone pairs available and then and H atom covalently bonded to the electronegative atom and close to another electronegative atom.
by Zoya Mulji 1K
Fri Nov 08, 2019 1:57 pm
Forum: *Liquid Structure (Viscosity, Surface Tension, Liquid Crystals, Ionic Liquids)
Topic: Polarizability and States
Replies: 3
Views: 48

Polarizability and States

What is the relationship between polarizability and the states of atoms/molecules?
by Zoya Mulji 1K
Fri Nov 08, 2019 11:50 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Electron Distortion
Replies: 2
Views: 18

Electron Distortion

What is the relationship between electron distortion and polarizability of the electron?
by Zoya Mulji 1K
Fri Nov 08, 2019 11:48 am
Forum: Interionic and Intermolecular Forces (Ion-Ion, Ion-Dipole, Dipole-Dipole, Dipole-Induced Dipole, Dispersion/Induced Dipole-Induced Dipole/London Forces, Hydrogen Bonding)
Topic: Interaction Potential Energy
Replies: 3
Views: 26

Interaction Potential Energy

Can someone explain the components of the formula for interaction potential energy and what the alpha and r means?
by Zoya Mulji 1K
Wed Oct 30, 2019 11:58 pm
Forum: Trends in The Periodic Table
Topic: Shielding and Electron Replusion
Replies: 3
Views: 35

Re: Shielding and Electron Replusion

shielding occurs across energy levels because the electrons in the energy levels that are closer to the nucleus block the electrons higher up from receiving the full charge. electron-electron repulsion occurs within the same energy level because when there are multiple electrons, they push each othe...
by Zoya Mulji 1K
Wed Oct 30, 2019 11:51 pm
Forum: Quantum Numbers and The H-Atom
Topic: 1D.19
Replies: 3
Views: 37

Re: 1D.19

to find orbitals you would use ml. the values can range from -l to +l so you would need to find l from n and then find the values for ml.
by Zoya Mulji 1K
Wed Oct 30, 2019 11:46 pm
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: When do you use a negative sign in the Bohr equation?
Replies: 7
Views: 56

Re: When do you use a negative sign in the Bohr equation?

the negative is always there in the equation because if we say that as n --> infinity, that E is 0, as the electron comes back down from high energy levels and approaches the nucleus, it loses energy and the values for energy are "negative." in a review session, a good analogy used was ......
by Zoya Mulji 1K
Wed Oct 30, 2019 11:41 pm
Forum: Photoelectric Effect
Topic: Increasing Light Intensity Photoelectric Effect
Replies: 7
Views: 38

Re: Increasing Light Intensity Photoelectric Effect

frequency determines whether or not electrons are emitted. the intensity increases the number of photons but not that actual energy.
by Zoya Mulji 1K
Wed Oct 30, 2019 11:39 pm
Forum: Formal Charge and Oxidation Numbers
Topic: Why does formal charge indicate stability?
Replies: 3
Views: 43

Re: Why does formal charge indicate stability?

since formal charge indicates the gain/loss of electrons while forming a covalent bond, it serves as a predictor for stability in a lewis structure. The structure with the least formal charge should be lower in energy and thereby be the better Lewis structure.
by Zoya Mulji 1K
Tue Oct 22, 2019 11:18 am
Forum: Trends in The Periodic Table
Topic: Ionic Radii
Replies: 10
Views: 81

Ionic Radii

Why are anions much bigger than their parent atoms/ why are cations much smaller?
by Zoya Mulji 1K
Tue Oct 22, 2019 11:15 am
Forum: Trends in The Periodic Table
Topic: Effective Nuclear Charge
Replies: 7
Views: 37

Re: Effective Nuclear Charge

example: with oxygen (+8), the outer electrons are being blocked from the full charge by the inner electrons. the inner electrons shield the outer electrons from the electrostatic attraction of a positive nucleus. the outer electrons feel a reduced electrostatic attraction and this results in an eff...
by Zoya Mulji 1K
Tue Oct 22, 2019 11:12 am
Forum: Trends in The Periodic Table
Topic: Electron Affinity
Replies: 4
Views: 32

Re: Electron Affinity

going off the previous answer, there is a high electron affinity for elements in the top right of the periodic table so it follows a similar trend to ionization energy in that it decreases down and group and increases across a period. this does exclude noble gases though because adding an electron t...
by Zoya Mulji 1K
Tue Oct 22, 2019 11:09 am
Forum: Trends in The Periodic Table
Topic: Ionization Energy Across a Period
Replies: 3
Views: 16

Ionization Energy Across a Period

I get that as you go down a group, the electrons get further away from the nucleus and are shielded by the inner electrons so the ionization energy decreases. Why does ionization energy increase across a period?
by Zoya Mulji 1K
Tue Oct 22, 2019 11:06 am
Forum: Trends in The Periodic Table
Topic: 2nd Ionization Energy
Replies: 7
Views: 44

Re: 2nd Ionization Energy

Something to also consider: the 1st ionization energy is easier because the atom would be neutral and when you remove an electron, the charge becomes positive and the attraction on that 2nd electron would be higher
by Zoya Mulji 1K
Fri Oct 18, 2019 11:19 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: removing electrons
Replies: 5
Views: 247

Re: removing electrons

You would need to pull from the outermost electrons so if you had 4d10 5s2 5p1 you would pull or add from 5p1 first and then if you need to pull more you would move on to 5s2. Pay attention to the numbers out in front of the orbitals and pull from the highest number first.
by Zoya Mulji 1K
Fri Oct 18, 2019 11:15 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: ION WITH +1
Replies: 4
Views: 247

Re: ION WITH +1

You would normally find the electron configuration and pretend like it does not have a + or -. After finding the normal electron configuration, you can go in and add or remove an electron. The only time you would not be able to look for the normal configuration in the periodic table is if you were l...
by Zoya Mulji 1K
Fri Oct 18, 2019 11:08 am
Forum: Electron Configurations for Multi-Electron Atoms
Topic: Total Coulombic potential energy
Replies: 2
Views: 40

Re: Total Coulombic potential energy

electrostatic potential energy is proportional to/ depends on ((q1)(q2))/ r where q1 is the charge 1, q2 is the charge 2, and r is distance. electrostatic energy goes up when the charge of the nucleus goes up and and goes down when the distance goes up because E and r are inversely proportional.
by Zoya Mulji 1K
Tue Oct 15, 2019 8:41 pm
Forum: Properties of Light
Topic: Electromagnetic Radiation
Replies: 3
Views: 28

Electromagnetic Radiation

What is the arrangement of following types of photons of electromagnetic radiation in order of increasing energy: g-rays, visible light, ultraviolet radiation, microwaves, x-rays?
by Zoya Mulji 1K
Tue Oct 15, 2019 8:22 pm
Forum: DeBroglie Equation
Topic: De Broglie's Equation
Replies: 17
Views: 110

Re: De Broglie's Equation

De Broglie suggested that the equation works for any particle with momentum, that has a rest mass, and has wavelike properties.
by Zoya Mulji 1K
Fri Oct 11, 2019 11:40 am
Forum: DeBroglie Equation
Topic: exhibiting wave-like properties
Replies: 4
Views: 270

Re: exhibiting wave-like properties

In lecture today, it was said that a particle with less than 10^-15m wavelength does not have detectable wavelength properties. If the mass is higher, it will have a smaller wavelength and therefore is more likely to only have particle-like behavior and not wave-like behavior.
by Zoya Mulji 1K
Fri Oct 11, 2019 11:37 am
Forum: DeBroglie Equation
Topic: Measurable V. Non-Measurable
Replies: 5
Views: 47

Measurable V. Non-Measurable

What wavelength values from De Broglie's equation indicate whether or not a particle or electron has detectable wavelength properties?
by Zoya Mulji 1K
Fri Oct 11, 2019 11:34 am
Forum: Accuracy, Precision, Mole, Other Definitions
Topic: Accuracy and Precision
Replies: 8
Views: 84

Re: Accuracy and Precision

accuracy indicates how close measurements are to the "true" or real value and precision indicates how close measurements are to each other, but not necessarily to the "true" value.
by Zoya Mulji 1K
Thu Oct 10, 2019 1:27 am
Forum: Properties of Electrons
Topic: Atomic Spectra and Energy Levels
Replies: 5
Views: 42

Atomic Spectra and Energy Levels

can someone elaborate on how spectroscopic analysis of light can be used to identify different elements?
by Zoya Mulji 1K
Thu Oct 10, 2019 1:24 am
Forum: SI Units, Unit Conversions
Topic: Angstrom
Replies: 16
Views: 202

Re: Angstrom

^ Also remember that we will get a formula/constants sheet for every test so a lot of the information we need will be given to us. There's no harm in memorizing though!
by Zoya Mulji 1K
Thu Oct 10, 2019 1:20 am
Forum: Bohr Frequency Condition, H-Atom , Atomic Spectroscopy
Topic: Bohr Frequency Condition
Replies: 1
Views: 39

Bohr Frequency Condition

Can someone explain how to do one of the learning outcomes in this section. It says we should know how to use the Bohr frequency condition to explain the origin of the lines in the spectrum of an element.
by Zoya Mulji 1K
Thu Oct 10, 2019 1:07 am
Forum: Limiting Reactant Calculations
Topic: Test 1
Replies: 11
Views: 162

Re: Test 1

^^ I would recommend pulling up the Review/Outline for Fundamentals that's on the website. Just go through the key concepts and make sure you know how to do a couple of types of problems from each bullet point.
by Zoya Mulji 1K
Thu Oct 03, 2019 3:05 am
Forum: SI Units, Unit Conversions
Topic: Question about final answers on tests
Replies: 8
Views: 119

Re: Question about final answers on tests

Usually, it should say "gaseous" or "solid" before the name of the compound to help indicate what state we should write in the equation.
by Zoya Mulji 1K
Thu Oct 03, 2019 3:00 am
Forum: Administrative Questions and Class Announcements
Topic: First Test in Discussion
Replies: 13
Views: 203

Re: First Test in Discussion

The test is supposed to be more like a quiz so I would probably just make sure I know how to do all of the fundamental homework problems on the syllabus.
by Zoya Mulji 1K
Thu Oct 03, 2019 2:42 am
Forum: Significant Figures
Topic: Sig Figs Rule
Replies: 2
Views: 62

Sig Figs Rule

What is rule for determining the number of sig figs to use in an answer?

Does it depend on the sig figs of the given information in the problem (ex. g of a compound) or does it depend on the molar mass you choose to use in the calculations?
by Zoya Mulji 1K
Tue Oct 01, 2019 2:21 pm
Forum: Balancing Chemical Reactions
Topic: Tips on what number to multiply the entire equation if needed
Replies: 8
Views: 122

Re: Tips on what number to multiply the entire equation if needed

Given one of the reactants is a hydrocarbon, start by multiplying the hydrocarbon (ex. C4H10) times two and then balancing the other reactants and products according to this. This method isn't necessary, but it prevents you from having to multiply/ deal with fractions at the end of the balancing pro...
by Zoya Mulji 1K
Tue Oct 01, 2019 2:13 pm
Forum: Balancing Chemical Reactions
Topic: Tips for Balancing Chemical Equations [ENDORSED]
Replies: 14
Views: 168

Re: Tips for Balancing Chemical Reactions [ENDORSED]

If the reactants include a hydrocarbon (ex. C4H10), I usually go ahead and start by doubling the hydrocarbon and then balancing all other pieces according to this. It helps to avoid getting fractions and having to double all of the stoichiometric coefficients later on.

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