Introduction to Biology and Chemistry: Exam Review and Key Concepts

Exam 1

DNA and RNA

DNA: A G T C

RNA: U C A G

Organic Molecules and Polymers

Most pesticides are organic molecules.

True or False: All cell walls are made of carbohydrates. True

True or False: All biomolecules are polymers. False

Redox Reactions and Electricity

True or False: A battery uses redox reactions to generate electricity. True

True or False: Oxidation and reduction have to happen together. True

True or False: The term “organic” when referring to molecules means they are not harmful. False

Review Questions

  1. True
Read More

Introduction to Chemistry: Ions, Reactions, and Radioactivity

Name & Formula

1. Phosphate Ion: PO43-

2. Nitrate Ion: NO3

3. Hydroxide Ion: OH

4. Carbonate Ion: CO32-

5. Ammonium Ion: NH4+

6. Potassium Oxide: K2O

7. Aluminum Sulfate: Al2(SO4)3

8. Calcium Iodide: CaI2

9. Phosphorus Trichloride: PCl3

10. Carbon Disulfide: CS2

Oxidation and Reduction

1. Oxidation is defined as: Loss of electrons

2. Reduction is defined as: Gain of electrons

Reaction Analysis: Cu + 2 AgNO3 ⟶ Cu(NO3)2 + 2 Ag

3. What is being oxidized? Cu

4. What is being reduced? Ag+ in AgNO3

5. Which way

Read More

Understanding Air Pollution, Climate Change, and Chemistry Fundamentals

Air Pollution and Climate Change

Understanding the Basics

1. Lewis Dot Structure for SO3

(Insert image of Lewis Dot Structure for SO3 here)

2. Electromagnetic Radiation

Electromagnetic radiation is energy in waves that travel at light speed.

3. Ozone Protection

Ozone protects us from ultraviolet radiation.

4. CFCs and Their Uses

CFCs (Chlorofluorocarbons) were used as refrigerants in air conditioners and propellants in spray cans. (Insert image of CFC structure here)

5. The Ozone Hole

The “hole” in the ozone

Read More

Understanding Chemical Reactions and Properties of Elements

Nascent Hydrogen

Nascent Hydrogen is a more energetic and powerful reductant than molecular hydrogen. Here’s why:

a. Reduction of Potassium Permanganate: Nascent Hydrogen reduces acidified potassium permanganate, decolorizing it, while ordinary hydrogen cannot.

Reaction: 2H2SO4 + 3KMnO4 + 10[H] → K2SO4 + 2MnSO4 + 8H2O

AND H2SO4 + KMnO4 + H2 → No Reaction

b. Reduction of Potassium Dichromate: Nascent hydrogen reduces acidified Potassium Dichromate solution, changing its color from orange to green,

Read More

Titration & Electrochemistry Experiments: A Comprehensive Guide

Titration and Electrochemistry Experiments

Acid-Base Titrations

3. Titration of Strong Acid with NaOH

This experiment involves titrating a strong acid (hydrochloric acid) with a strong base (sodium hydroxide).

  1. Measure 10ml of an unknown HCl solution into a titrating flask.
  2. Add 3 drops of methyl orange indicator.
  3. Fill a buret with 0.1 N NaOH.
  4. Titrate the unknown HCl until the color changes to radish-yellow.
  5. Repeat the experiment twice.
  6. Use the mean value for calculations.

4. Titration of Acetic Acid with NaOH

This

Read More

Chemistry Basics: Key Concepts and Formulas

Chemistry Basics

Fundamental Concepts

Chemical Reactions

Synthesis: A + B -> AB
Decomposition: AB -> A + B
Single Displacement: A + BC -> AC + B
Double Displacement: AB + CD -> AD + CB

Avogadro’s Number and Molecular Mass

Avogadro’s Number: 6.022 x 1023
Molecular Mass: The number under the element symbol (amu)
Formula Mass: Sum of atomic masses of all elements in a compound
Molar Mass: Mass of one mole of a substance (grams)

Calculating Moles and Mass

Moles in grams: Divide grams by molar mass (amu)

Read More