Notes, summaries, assignments, exams, and exercises for Chemistry for Baccalaureate

What is an atom?

Atoms are the basic units of matter and the defining structure of elements.

What is an electron?

A subatomic particle with a charge of negative electricity.

What is the nucleus of an atom made of?

Is made up of protons and neutrons.

What is a proton?

Elemental particle of the nucleus of the atom and that has a positive electric charge.

What is a neutron?

A subatomic particle of about the same mass as a proton but without an electric charge.

Where is the mass of an atom concentrated?

In the nucleus most of 99.9% of the mass is concentrated here.

An atom is mostly empty space?

Yes.

What is the function of neutrons?

To allow protons to be together.

What surrounds the nucleus of an atom?

The nucleus is surrounded by electron clouds that produce...

Water Quality Definitions

Alkalinity

Alkalinity: A measure of the water’s capability to absorb hydrogen ions without significant pH change (buffering capacity).

Problem 7-4: Settling Tank Design for Stillwater Water Plant Expansion

Design the settling tank(s) for the City of Stillwater’s water treatment plant expansion using the design overflow rate found in Example 7-3. The maximum day design flow is 0.5 m³/s. Assume a water temperature of 10° C.

Design Calculation Steps (Set 1)

1. Find the Surface Area

   Calculation: (0.5 m³/s) × (86,400 s/d) = 43,200 m³/d

2. Select the Number of Tanks

   

   = 221.66 or 222 m²/tank

3. Select a Trial Width for Calculation

   The maximum width for the chain-and-flight sludge collector is 6 m increments. Assume a width of 4 m.

4. Check

Fatty Acid Classification: Saturated, Monounsaturated, and Polyunsaturated

Fatty acids are the main components of triglycerides and phospholipids. They are non-polar and therefore hydrophobic. Their chains consist of covalently bonded carbon atoms with hydrogen atoms.

Saturated fatty acids contain only single bonds, meaning they are "saturated" with hydrogen. Unsaturated fatty acids, conversely, contain one or more double bonds.

Saturated Fatty Acid	Monounsaturated Fatty Acid	Polyunsaturated Fatty Acid

Cis vs. Trans Unsaturated Fatty Acid Isomers

• If hydrogen atoms are on the same side of the double bond, the isomer is cis (e.g., yellow H in diagrams). If hydrogens are on the opposite side of the double bond, the isomer is trans.
• Cis fatty acids have

Chemistry Fundamentals

Arranging the Elements: The Periodic Table

• Organizing the elements according to their properties.
• Dmitri Mendeleev discovered a pattern to the elements in 1869.
• Periodic means “happening at regular intervals.”
• Mendeleev found that element properties follow a pattern that repeated every 7 elements.
• He found that elements yet to be found would fill the gaps. By 1886, all of the gaps had been filled.
• In 1914, Henry Moseley determined the number of protons. Elements were arranged by atomic number. The Periodic Law states that the repeating physical and chemical properties of elements change periodically with the element's atomic number.

Classifying Elements on the Periodic Table

• Metals: Found to the left of the zigzag line on

Stoichiometry, Yields and Reaction Types

Solution

Solution — This is obtained when one chemical becomes completely dissolved in another.

Theoretical Yield

Theoretical yield — If a chemist calculates the maximum amount of product that could be obtained in a chemical reaction, he or she is calculating the theoretical yield.

Stoichiometry

Stoichiometry — Terms used to designate the calculations of quantities of substances involved in chemical reactions.

Percent Yield

Percent yield — This is obtained by dividing the actual yield by the theoretical yield and multiplying by 100%.

Limiting Reactant

Limiting reactant — The reactant that is fully consumed during the reaction.

Practice Questions

1.1 — In the equation 6 CO₂ + 6 H₂O ... the mole ratio...

Impact of Minimum CD & Treasury Bond Investment

Question: If the amount invested in CDs and treasury bonds is at least $5,000 plus 1.2 times the amount invested in municipal bonds and growth stocks, what is the new optimal solution and Optimal Feasible Value (OFV)?

Answer: Since the allowable increase is greater than $5,000 and this is a binding constraint, you must re-solve the problem to obtain the new optimal solution. The new OFV can be estimated using the shadow price: New OFV ≈ Old OFV + 5000 * (-0.0295).

Adding a GIC Investment Alternative

Question: If there is another investment alternative in Guaranteed Investment Certificates (GICs) with a Return on Investment (ROI) of 10%, what is the new optimal solution and OFV?

Answer: Introducing...

Advanced Materials Science Concepts

High Entropy Alloys (HEAs)

What Materials Are Named ‘High Entropy Alloys’?

Substances constructed with equal or nearly equal quantities of five or more metals. They exhibit a higher degree of fracture resistance, tensile strength, as well as corrosion and oxidation resistance compared to conventional alloys.

What Conditions Must Be Satisfied to Obtain HEA from a Number of Chemical Elements?

Gibb’s phase rule applies: F=C-P+2.

Graphene and Graphene-Like Materials

Differences Between Graphene and Silicene

Silicene is not flat; it is stronger than graphene. Silicene’s hydrogenation reaction is more exothermic than graphene’s.

Three Examples of Graphene-Like Materials

• Layered van der Waals materials
• Graphene-like

Ethers and Epoxides: Reactions, Properties, and Applications

1. Boiling Point Difference: Ethanol vs. Dimethyl Ether

Question: Which provides the best explanation for the large boiling point difference between ethanol (b.p. 78 °C) and dimethyl ether (b.p. -25 °C)?

Correct Answer: The difference in hydrogen bonding (H-bonding).

Note: The molecular weight of both ethanol and dimethyl ether is 46. The significant difference in boiling points is due to ethanol's ability to form strong intermolecular hydrogen bonds, which dimethyl ether cannot.

2. Utility of Crown Ethers

Question: Crown ethers are especially useful for:

Correct Answer: Complexing with metal cations.

3. Product of Cyclohexene and Peroxybenzoic Acid

Question: What is the product of the reaction...

Biography of Antoine Lavoisier

Antoine Lavoisier was a French chemist born on August 26, 1743, in Paris. He was one of the primary protagonists of the scientific revolution that led to the consolidation of chemistry; thus, he is considered the founder of modern chemistry. He studied law, although his activities began to focus on scientific research. He was elected to the Academy of Sciences in 1768.

Public Service and Reforms

He held various public offices, including:

• State Director of Gunpowder (1776)
• Member of the committee to establish a uniform system of weights (1790)
• Commissioner of the Treasury (1791)

Lavoisier also tried to introduce reforms in the French monetary and tax systems, as well as methods of agricultural production.

Scientific Contributions

Hess's Law and Enthalpy Diagrams

Hess's Law: If a reaction occurs at several stages, whether real or theoretical, the total enthalpy change is equal to the sum of the enthalpies of reaction of these intermediate reactions.

An enthalpy diagram represents the energies at play in a chemical reaction using activated complex theory. According to this theory, when the reactants approach, there is an intermediate state of high energy and short duration, which is the activated complex.

In these diagrams, we can represent the activation energy, which is the energy needed for reactant molecules to absorb to form the activated complex. A slow reaction has a high activation energy, while a quick reaction will have a low activation energy.

Entropy and Molecular