CHEM 1A
Extra Practice on Significant Figures
Converting to moles
Edited by Viktor Kunder, chemistry tutor, 01/12/2018
One of the most important topics in chemistry is conversions, especially of atoms, grams, and moles. This video will take you through examples that you will not only teach you, but you can also practice at the same time. At the end of the video answer:
How many moles is 14g of carbon?
How many atoms is 2 moles of carbon?
Moles, molecules and gram.docxMore practice on conversion between moles, molecules/atoms and grams
Use the worksheet to check your understanding and test your knowledge!
Added by Preet Kaur, Fall 2020
Atomic Number, Mass Number and Net charge
Knowing the relationships between the atomic mass, mass number and net charge are important in chemistry. These tends to create confusion to the students due to rhyming words. This video explains the relationship between protons, neutrons, mass number and net charge.
Added by Preet Kaur, Fall 2020
Protons, Neutrons and Net charge (Practice)
Use the following table to fill in the blanks and understand the relationship between the protons, neutrons, electrons and net charge.
If you need help, watch the video on top :)
Added by Preet Kaur, Fall 2020
Ionic Formulas
Writing ionic formulas can be challenging and confusing due to subscripts and charges. This video goes in depth on how to write ionic formulas.
Test yourself:
Write molecular equation for Potassium Phosphate and Magnesium Nitrate
Added by Preet Kaur (Fall 2020)
Net Ionic Equations
This video gives overview of how to write net ionic equations step by step. It is recommended you watch the video above (Writing ionic formulas) before watching this! Take notes!!
Test yourself:
Write net ionic equations for:
Magnesium nitrate and strontium chloride
Magnesium nitrate and lithium sulfate
Added by Preet Kaur (Fall 2020)
Nomenclature Worksheet
Nomenclature Worksheet.docxPolyatomic Ions
I found that the best way to become comfortable with all the ions, their charges, and their names is to use them and repeat them to myself over and over again. So, I made this puzzle so that it will hopefully be just a tad bit more fun for those who need a little more time with these strange ions.
Identifying the Different Types of Reactions
I highly recommend that you take the time to do these worksheets. There are concepts shown that will help you determine the type of reaction with a quick glance. That skill is very helpful in tests when you have limited time.
Electron and Molecular Geometry Practice
Hopefully more practice than is necessary to cement the concept for you.
CHEMICAL BONDING
08/16/17 Myrka & Lizbeth
Goals this week with the Chemistry tutors:
do practice problems without using your notes
discuss how to study for this topic
ask the tutor how to make flash cards
discuss how to take and study from practice tests
understand and be able to explain the difference between the three bond types
use what you've learned to predict what bond will form between two atoms
Activities to do at home:
Create a venn diagram analyzing the similarities and differences between the bonds
make flash cards
summarize the lecture into 5 sentences
work on homework
watch the above khan academy video
When talking about bonds, there are three major types you will see in this class: ionic, covalent, and metallic bonds.
Ionic bonds transfer electrons from an atom with low electronegativity to an atom with a high electronegativity (e.g. Na + Cl --> Na+ + Cl-)
Covalent bonds share electrons evenly in the bond (e.g. O=C=O in CO2)
Metallic bonds = the attraction between metal ions and delocalized ("free" electrons). (e.g. multiple Fe atoms existing near each other)
Learning and mastering the types of bonds is imperative in Chemistry, and provides a foundation for more complicated Chemistry concepts.
This is a great video that talks about intermolecular forces. When watching the video be sure to take notes actively. At the end of the video be sure you are able to answer:
What intermolecular forces does NH3 and H2O have when in solution?
What makes H2O polar?
What increases the boiling point?
Why do people put salt on icy roads?
Be sure to answer these questions as they do have a very important concept behind them. Also, feel free to ask a tutor for help!
INTERMOLECULAR FORCES
Intermolecular Forces and Boiling Points
Edited by Viktor, chemistry tutor, 8/23/17
One of the most practical topics in chemistry is intermolecular forces. It is a high yielded test question and very important to know. This video does a great job explaining the concept, but if you need any clarification, be sure to seeks help from the Chemistry tutors in the Learning Center. At the end of the video, be able to answer:
If salt was put on ice, what happens to the boiling and freezing point?
What types of intermolecular forces does water have?
PERIODIC TRENDS AND PROPERTIES
Edited by Myrka Macedo, Monthly Project #1, 10/1/2017
Goals this week with the Chemistry tutors:
Be able to recognize the direction of the periodic trends
Understand the physical properties relating to the trends
Be able to explain how the trends relate to one another
Ex: "How does electron affinity/electronegativity of the atom help explain the chemical reactivity trend?"
Practice Problems:
For each of the following pair of atoms, determine which is larger and explain why. Draw a picture of the shells if needed.
Carbon or Oxygen?
Lithium or Bromine?
Magnesium or Calcium?
For each of the following pair of atoms, determine which can lose an electron easier and explain why. (Is this a lower or higher ionization energy?)
Hydrogen or Helium?
Boron or Aluminum?
When learning the periodic table trends, it is important to understand why these physical properties of the elements occur.
Ionization Energy: the energy needed to remove an electron
down a group decreases as valence electrons are farther from the nucleus, thus less pulling power by the protons and less energy needed to remove an electron
across a period increases as the atoms are getting closer to the octet rule (Gaining stability like a Noble Gas)
Atomic Radius
down a group increases as each next period has additional electron shells, each farther away from the pull of the protons
across a period decreases as there are more protons to pull electrons in the shells closer
Electron Affinity: energy to attract electrons
down a group decreases as there is less attraction towards electrons due to greater amount of shells, which are father away from the proton pull
across a period increases as wants to complete the octet rule and gain stability
Electronegativity: attraction between the nucleus and electrons of the atom
down a group decreases as valence electrons are farther from protons in the nucleus
across a period increases as the number of protons in the nucleus increases
Chemical Reactivity: Metals
down a group reactivity increases due to increase of electron shells, making it easier for electrons to be given or taken away
across a period reactivity decreases as it is less likely to give away electrons due to it being closer to completing the octet rule and gaining stability
Chem 1A Mock Exam on Midterm 1 (Monthly Project 1)
https://fresnostate.co1.qualtrics.com/jfe/form/SV_26ac9vWjbSlxfm
Created by - Tanner Melton & Manharsh S Sekhon on 09/30/2017
TOPICS that we need to work on
Gases
Thermochemistry
The Quantum- Mechanical Model
Lewis Model
Overview of Lab Practical Calculations
Created by Myrka Macedo, Monthly Project #2, 10/31/17
After standardization, you now have the exact molarity of the KMnO4 titrant. You will use this molarity to find the moles of Oxalic Acid in the unknown. Notice how the calculations for finding the percent Oxalic Acid in the unknown is similar to the standardization calculations.
Questions to ask yourself during the practical calculations:
Why do you titrate to the equivalence point?
What is the purpose of the standardization procedure?
During standardization which reactant is limiting and which is in excess?
What is your mole to mole ratio used for the calculations?
Once you have completed reviewing these calculations and have asked yourself these questions, feel free to ask any of the Chemistry Tutors for help.