Notes, summaries, assignments, exams, and problems for Chemistry

Intermolecular Forces (IMFs)

IMFs include: Covalent, Hydrogen, Metallic, Dipole, London, and Ion interactions.

Solution Chemistry Formulas

• pH (Acidic Solutions): $\text{pH} = -\log[\text{H}^+] = -\log N = \text{p}H_A = \sqrt{K_a M}$ (where $K_a = x^2/M$ and $-\log x = \text{p}OH$ is incorrect in this context, use $\text{pH} = 14 - \text{pOH}$)
• pOH (Basic Solutions): $\text{pOH} = -\log[\text{OH}^-] = -\log N$. For weak bases (WB): $K_b = x^2/M$ and $-\log x = \text{pOH}$, leading to $\text{pH} = 14 - \text{pOH}$.

Strong Acids

Common strong acids include: $\text{HNO}_3$, $\text{H}_2\text{SO}_4$, $\text{HBr}$, $\text{HI}$, $\text{HClO}_4$, and $\text{HClO}_3$.

Lewis Acid

A compound or ionic species that can accept an electron pair from a donor compound.... Continue reading "Chemical Bonding and Solution Chemistry Concepts" »

1.Who propossed the theory of One-dimensional consolidation? Karl Terzaghi

2.What types of permeameters exist in Lab tests? Constant head permeameter and Failing head permeameter

3.What is the name of the equation that Governs the 2D underground flow? Laplace’s Equation.

4.Name of the method of draw flow nets That uses iterative calculations. Finite Differences

5.What are the units of the compression Index Cc? Adimensional, NOT UNITS

6.Describe boiling in soils. Boiling of soils occurs when there is an Upward flow and the seepage force is greater that the submerged weight of the Soil.

7.What are the assumptions in laplace’s Equation. Darcy’s law applies, Water and Solids are uncompressible

8.When in it better to use failing head permeameter?

Water Quality and Treatment Fundamentals

1. Eutrophication

What does the term eutrophication refer to?
An excess of algae growth due to inorganic nutrients.

2. Turbidity and Solubility

What type of particles are responsible for turbidity?
Particulate non-settleable compounds.

If the partial pressure of a gas increases, the solubility in water of the gas:
Increases.

3. Environmental Impacts

Which of the following is an effect of eutrophication?

• Increase of pH in water where there is eutrophication.
• Bacteria consume the oxygen in water by degrading dead plants.
• Plants do not grow due to a lack of sunlight.

Which of the following is an effect of thermal pollution?
Lack of O₂ due to lower solubility of gases at high temperatures.

4. Water Chemistry and Directives

What

Q#9.1: How order of reaction is experimentally determined.

Ans. Order of reaction is determined by the following two methods.

1. From Rate Law.

   In this method, the rate of reaction is measured using chemical and physical methods (volumetric, gravimetric, spectrophotometer, pH-meter, conductometric methods). The dependence of the rate of reaction on the concentration of reactants tells us about the order of reaction. For example, a reaction in which the rate of reaction doubles when the concentration of reactants is doubled will be of first order. If the rate increases four times by doubling the concentration, the reaction will be of second order.

2. Ostwald’s Isolation Or Large Excess Method.

   This method is used to determine the order of complicated

Photoelectric Effect Explained

The photoelectric effect is the emission of electrons or other free carriers when light shines on a material. Electrons emitted in this manner are called photoelectrons.

Specifically, when light shines on a metal, electrons can be ejected from its surface. This phenomenon, where light waves hitting a metal surface cause electrons to be ejected, is a fundamental aspect of the photoelectric effect.

Chemical Bonds: Types and Strengths

Understanding Chemical Bonds: Strongest to Weakest

Chemical bonds are the forces that hold atoms together to form molecules. Here are three types, generally ordered from strongest to weakest:

1. Ionic Bonding

   Ionic bonding involves a transfer of an electron, where one atom gains an electron while

Questions

Answers

Why do you use distilled water in your experiments?

Because distilled water has all its impurities removed through distillation.

What is the formula for converting oC to Fahrenheit( F)?

(oC x 1.8) + 32

Formula for converting oF into Celsius

 (oF - 32)  1.8

Formula for converting oC to Kelvin(K)

K = oC + 273.15

Name all the volumetric apparatus used in the lab

Beaker, measuring cylinder, Burette, Pipet, and volumetric flask. (See the attachment)

A student got the following results in his experiment: 14.9g, 14.19g, 14.88g, 14.92g, but the actual weight is 20.90g. How accurate are the student results. And how precise are the results.

The student results are not accurate but precise. Has the precision of  0.05g

Sketch 2 pieces of glassware:

Kinetic Energy and the Nature of Matter

• Kinetic Energy: The energy an object possesses due to its motion.
• Kinetic Theory: States that all matter is composed of tiny particles in constant motion.

Pressure and Its Measurement

• Gas Pressure: Results from the force exerted by a gas per unit surface area of an object.
• Vacuum: An empty space devoid of particles and pressure.
• Atmospheric Pressure: Arises from the collisions of atoms and molecules in the air with objects.
• Barometer: A device used to measure atmospheric pressure.
• Pascal (Pa): The SI unit of pressure.
• Standard Atmosphere (atm): The pressure required to support 760 mm of mercury in a mercury barometer at 25ºC.

Phase Transitions and States of Matter

• Vaporization: The conversion of a liquid to a gas