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General Chemistry

General Chemistry is the theoretical study of fundamental physical principles as they apply to chemical phenomena. It examines the applicability of these principles on a broad spectrum of topics which include atomic and molecular structure, bonding and modern quantum theory. Thus, General Chemistry serves not only as an introduction, but also an essential cornerstone for other chemistry disciplines.

General Chemistry explores the basic rules and properties of atoms, which are the basic units of matter. The primary challenge of studying General Chemistry is knowing when to apply the different rules and properties within varying chemical contexts. Such understanding can help predict how a particular atom will react under a particular condition, and even the eventual outcome of different chemical reactions. In addition to individual atomic properties, General Chemistry also aims to examine how atoms interact with each other, whether they attract or repel, and the conditions which permit the formations of different bonds. Thus, this knowledge is essential for successful theoretical prediction of atomic behavior.

General Chemistry is not limited to atomic theory, as it also explores modern quantum theory in different chemical systems. Entities smaller than atoms are considered and their properties in these sub-atomic levels can be examined, in addition to atomic behavior, to help predict chemical phenomena in the different branches of chemistry.

Categories within General Chemistry

Bonding

Postings: 247

Bonding is the process of forming chemical bonds due to the attractive interactions of different atoms.

Modern Quantum Theory

Postings: 92

Modern Quantum Theory is the theoretical foundation of physics which helps explain the chemical behavior of matter at both the atomic and subatomic levels.

Scientific Notation

Postings: 5

Scientific Notation refers to a method of condensing either very large or very small numbers into decimal form.

Writing aim and conclusions in a report

Aim 1. To determine the mole ratio of barium chloride to water in a hydrated barium chloride that BaCl2: H2O. Measure the mass before heating. Use heat For hydrate, and To find the mass of water measured after heating, and subtract the two masses to get mass of water. To convert mass into moles by using mass of wa

Atomic theory of matter

Please see attachment Question 27 The atomic and mass numbers for four different atoms are given below. Which two are isotopes of the same element? Atom Atomic Number Mass Number A 100 257 B 101 257 C 101 260 D 102 259 A and B B and C B and D C and D Question 30 Describe at least two experiments,

Energy Shell

For the following atoms in their ground state, determine the number of electrons in each energy shell. If there are no electrons in the particular energy shell, leave that answer box blank. (Please see attached file

Analysis of Atomic Radius variation with Z and period

03.03 Periodic Trends: Assignment Details For this assignment, you will be creating two graphs to show the trends of atomic radius across the periods and down a group on the periodic table. Then you will use your graph and what you have learned in the lesson to answer questions. Part I: Atomic Radius Trend Going Across the P

Properties of your chosen element

you are going to investigate an element of your choice. Once you have chosen and researched your element, you will create a presentation using powerpoint or Word document . Your presentation should include the following information: • the element's name and the origin of its name • the element's symbol, atomic number, and

Covalent and Ionic Bonding

Research the answers to the following questions on the internet and write your answers in your own words. For each answer, include the address of the web site (or title and author of a book or article) that you used to help you answer the question. 1. Which type of compound usually has higher melting points: ionic compounds o

Decomposition and Synthesis Reactions

Question 1 (Essay) Write the complete balanced equation for the reaction between barium metal (Ba) and nitrogen gas (N2). You do not need to make the subscripts smaller; just write them out as regular numbers. For example: N2. Question 2 (Multiple Choice) Which of the following is a product formed when NaCl decomp

Plant Growth Experiment

Katherine wants to investigate if the time of day a plant is watered affects the growth of the plant. She hypothesizes that a plant watered in the morning will grow faster than a plant watered at other times of the day. Identify the specific independent and dependent variables that will be involved in an experiment to test t

Graphing: Solubility

Unit 3 Methods: Solutions Graphing: Solubility Question Answer What do the numbers on the y-axis represent? What does each curve on the graph represent? Which substances show increasing solubility with increasing temperature? Which substances show decreasing solubility with increasing temperature? Which salt is

Voltaic Cell EMF: numerical problems

1. Using data in Appendix E, calculate the standard emf for each of the following reactions: (a) H2(g) + F2(g) → 2 H+(aq) + 2 F-(aq) (b) Cu2+(aq) + Ca(s) → Cu(s) + Ca2+(aq) (c) 3 Fe2+(aq) → Fe(s) + 2 Fe3+(aq) (d) 2 ClO3-(aq) + 10 Br-(aq) + 12 H+(aq) → Cl2(g) + 5 Br2(l) + 6 H2O(l) 2. Using the standard reduction po

Redox Reactions and Voltaic Cell

Complete and balance the following equations, and identify the oxidizing and reducing agents. (Recall that the O atoms in hydrogen peroxide, H2O2, have an atypical oxidation state.) (a) NO2-(aq) + Cr2O72-(aq) → Cr3+ (aq) + NO3-(aq) (acidic solution) (b) S(s) + HNO3(aq) → H2SO3(aq) + N2O(g) (acidic solution) (c) Cr2O72-(

Acid-Base Reactions, Buffer and Thermodynamics

I am stuck on a few chemistry questions. Please help. 17.16) Use information from Appendix D to calculate the pH of (a) a solution that is 0.250 M in sodium formate (HCOONa) and 0.100 M in formic acid (HCOOH); (b) a solution that is 0.510 M in pyridine (C5H5N) and 0.450 M in pyridinium chloride (C5H5NHCl); (c) a solution that

Le Chateliers Principle Lab

Observations: 1 1mL Ba(NO3)2 + 0.5mL K2CrO4 + drops HCl? + drops NaOH? "Ba(NO3)2=clear and colourless Ba(NO3)2 + K2CrO4= yellow turbid solution (precipitate) HCl= clear yellow solution (precipitate dissolved) NaOH= yellowish turbid solution (precipitate returns by neutralizing acid) " 2 1mL Ba(NO3)2 + 0.5mL K2Cr2O7 + 10 d

Kinematics: Rate Law and Rate Constant

Consider the reaction of peroxydisulfate ion S2O8 ^2 - with iodide ion (I-) in aqueous solution: S2O8^2-(aq) + 3I-(aq)  2SO4 ^2-(aq) + I3-(aq) At a particular temperature the initial rate of disappearance of S2O8^2- varies with reactant concentrations in the following manner: Experiment [S2O8 2-] (M) [I-] (M) Initial Rat

The Enthalpy Change of a Chemical Reaction

The following are the givens from the experiment: Experiment 1: Measuring the Calorimeter Constant Temperature of the Calorimeter = 21.5C Temperature of Calorimeter after adding the water from the flask from bath= 39.2C Experiment 2: Enthalpy Change of a Chemical Reaction (3 Trials) Trial #1 Mass of empty Caloriometer

Molar Volume of an Ideal Gas Lab

Part 1 The following are the givens from the experiment: Initial Experiment with 10mL- 6 M HCl and 0.25g Zinc Initial Teperature = 21.5C Initial Pressure = 1.00atm After adding 0.25g Zinc - The solution reacted Pressue = 1.69atm Temperature = 27.3C Volume in Syrenge = 92.2mL Volume in Flask = 9.9mL Part 2 Repeated E

Lab: Empirical Formula of Copper Oxide

Step 1 = 5g of copper sulfate pentahydrate added to 50mL beaker Mass of beaker & contents = 90.000g Step 2 = add 30mL water to copper sulfate pentahydrate mass= 120.000g Step 3 = Add 10mL 6M Sodium Hydroxide Observed that the mass increased to 131.273g Mass of empty test tube = 27.400g Mass of test tube after heating =

Drawing structures for alkanes

Organic Chemistry Part IV 1- Draw a structure for each alkane. A- 2,2-dimethylpentane B- 3-isopropylheptane 2- What is the name of the following organic compound? CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 Spell out the name of the compound. 3- What is the name of the following organic compound? CH 3 CH 2 CCCH 2 CH 2 CH 3

Molecular formulas for alkanes

Organic Chemistry Part III 1- Consider the alkane shown in the model. A- What is the molecular formula for the alkane shown in the model? Express your answer as a chemical formula. B- Name the alkane shown in the model. Express your answer as the IUPAC name. C- Draw the structure of the cycloalkane 1,4-dimethylcyclohexan

Five Radioactivity and Nuclear Chemistry Questions

1- An injection containing 10.0pg 10 5 B was injected into a patient suffering from a brain tumor. The patient was irradiated by a neutron gun at the site of the tumor. Calculate the amount of energy released in megaelectronvolts given that 931 MeV is released for each 1 amu mass defect. To calculate the energy released, conside

Radioactivity and Nuclear Chemistry Discussion

1- BNCT relies on the initial targeting of tumor cells by an appropriate chemical compound tagged with 10 5 B , which preferentially concentrates in tumor cells. During the irradiation of the tumor site by neutrons ( 1 0 n ) the 10 5 B absorbs a low-energy neutron ( 1 0 n ), and it ejects an energetic short-range alpha part

Problems About Radioactivity and Nuclear Chemistry

1. At 8:00 a.m., a patient receives a 58-mg dose of I -131 to obtain an image of her thyroid. If the nuclide has a half-life of 8 days, what mass of the nuclide remains in the patient at 5:00 p.m. the next day? (Assume no excretion of the nuclide from the body). Express your answer using two significant figures. 2. A radioac

Radioactivity and Nuclear Chemistry Questions

1. What is the correct name for the compound depicted in the skeletal structure below? (See attached file for diagrams) 2. Which of the following is a structural isomer of 2-methylpentane? Choose from: cyclohexane 2-methyloctane 2,2-dimethylbutane 3-ethylheptane n-butane 3. How many of the carbons in the molecule de

Electrochemistry: Structures and Chirality

1. What is the correct name for the compound depicted in the skeletal structure below? (see attachment) 2. Which of the following is a structural isomer of 3-ethylheptane? Choose from: 2-methylbutane cyclohexane 3,4-dimethylpentane 3-ethylnonane 4-methyloctane 3. How many of the carbons in the molecule depicted belo

Problems on Electrochemistry

Electrochemistry Part IV 1- When the following equation is correctly balanced in acidic solution, how many electrons are transferred? 2- What is the oxidation state of C in the CF4 molecule? 3- Which species is being reduced in the following reaction: 4- Calculate E°cell for the following redox reaction. Zn2+

Electrochemistry and Balancing Redox Equations

Electrochemistry Part III 1- Balance each redox reaction occurring in acidic aqueous solution. Express your answer as a chemical equation. Identify all of the phases in your answer. Ni(s)+Cd 2+ (aq)→Ni 2+ (aq)+Cd(s) Ni(s)+Cd 2+ (aq)→Ni 2+ (aq)+Cd(s) MnO 4 − (aq)+Al(s)→Mn 2+ (aq)+Al 3+ (aq) 2- Balance each r

Electrochemistry: Numerical Problems

1- What mass of Cu(s) is electroplated by running 28.5A of current through a Cu 2+ (aq) solution for 4.00 h ?Express your answer to three significant figures and include the appropriate units. 2-How many minutes will it take to electroplate 60.1g of gold by running 5.00 A of current through a solution of Au + (aq) ?Expre

Electrochemistry- salt, voltaic cells and oxidation-reduction

1. Why do cars rust quickly in cold climates where the roads are deiced by the spreading of salt? Choose from: The combination of low temperature and the presence of ions makes the redox reaction for forming rust more favorable. The salt acts as the cathode to complete the "cell." The salt promotes the formation of hydron

Entropy Changes and Equilibrium states

See Attachment for questions and Data CHM4 1- Calculate the standard entropy change for the reaction 2Na(s)+Cl 2 (g)→2NaCl(s) using the data from the following table: Substance ΔH ∘ f (kJ/mol) ΔG ∘ f (kJ/mol) S ∘ [J/(K⋅mol)] Na(s) 0.00 0.00 51.30 Cl 2 (g) 0.00 0.00 223.1 NaCl(s) -411.0 -