CH117D: Introduction to General, Organic, and Biological Chemistry – Chapter 1 Study Notes

General, Organic, and Biological Chemistry: Chapter 1 Study Notes

Introduction to CH117D

This course, CH117D, introduces students to the foundational concepts of General, Organic, and Biological (GOB) Chemistry. The material is designed for students pursuing health sciences and related fields, focusing on the chemical principles that underpin biological and medical processes.

Matter and Its Classification

Definition of Matter

• Matter is anything that takes up space and has mass.

• All substances in the universe are forms of matter.

Types of Matter

• Pure Substances: Composed of only one type of particle. Can be represented by a single chemical formula or symbol.

• Mixtures: Combinations of two or more substances that can be separated by physical means.

Classification Table

Type	Definition	Examples
Element	Simplest type of matter, made of one kind of atom	O2, Fe, H2
Compound	Pure substance of two or more elements chemically joined	H2O, NaCl
Homogeneous Mixture	Uniform composition throughout	Salt water, air
Heterogeneous Mixture	Non-uniform composition	Salad, rocky road ice cream

Key Terms

• Atom: The smallest unit of an element that retains its properties.

• Element: A pure substance made of only one kind of atom.

• Compound: A pure substance made from two or more elements chemically bonded in a fixed ratio.

• Mixture: A physical blend of two or more substances.

Examples

• Cake batter: Mixture (heterogeneous if not fully mixed)

• Helium gas in a balloon: Pure substance (element)

• Olive oil: Homogeneous mixture

• Rocky road ice cream: Heterogeneous mixture

Elements, Compounds, and the Periodic Table

The Periodic Table Structure

• Groups: Vertical columns; elements in a group have similar chemical properties. Labeled 1-18 (IUPAC system), or with A/B designations.

• Periods: Horizontal rows, numbered 1-7.

• Metals, Nonmetals, Metalloids: Separated by a staircase line starting at boron. Metalloids border this line (except aluminum).

Elements Essential for Human Health

• Macronutrients: Needed in >100 mg/day (e.g., Na, Mg, K, Ca, Cl).

• Micronutrients: Needed in <100 mg/day (e.g., I, F, Fe, Zn).

• Major elements in biological molecules: C, H, O, N.

Chemical Formulas

• Show the elements and the number of atoms in a compound.

• Example: Water ($H_2O$) has 2 hydrogen and 1 oxygen atom.

• Example: Acetic acid ($C_2H_4O_2$) has 2 carbon, 4 hydrogen, and 2 oxygen atoms.

How Matter Changes

Physical vs. Chemical Changes

• Physical Change: Alters the form or appearance, not the identity (e.g., melting, boiling).

• Chemical Change: Alters the chemical identity; new substances are formed (e.g., rusting, burning).

Chemical Equations

• Represent chemical reactions using formulas and symbols.

• Reactants are on the left, products on the right.

• Arrow ($\rightarrow$) means "react to form".

• Physical states: (s) solid, (l) liquid, (g) gas, (aq) aqueous.

Balancing Chemical Equations

• Law of Conservation of Mass: Matter is neither created nor destroyed.

• Number of atoms of each element must be equal on both sides.

• Add coefficients to balance equations.

Example:

• Unbalanced: $H_2 + O_2 \rightarrow H_2O$

• Balanced: $2H_2 + O_2 \rightarrow 2H_2O$

Measurement in Chemistry

SI Units and Metric Prefixes

• Mass: kilogram (kg)

• Volume: liter (L)

• Length: meter (m)

Common Metric Prefixes

Prefix	Symbol	Factor
Giga	G	$10^9$
Mega	M	$10^6$
Kilo	k	$10^3$
Deci	d	$10^{-1}$
Centi	c	$10^{-2}$
Milli	m	$10^{-3}$
Micro	\mu	$10^{-6}$
Nano	n	$10^{-9}$
Pico	p	$10^{-12}$

Unit Conversions and Dimensional Analysis

• Use conversion factors to change units.

• Set up problems so units cancel, leaving the desired unit.

Example: Convert 450 mg to grams:

• $1\,g = 1000\,mg$

• $450\,mg \times \frac{1\,g}{1000\,mg} = 0.450\,g$

Significant Figures

• All nonzero digits are significant.

• Zeros between nonzero digits are significant.

• Leading zeros are not significant.

• Trailing zeros are significant only if there is a decimal point.

• Exact numbers (from definitions or counting) have infinite significant figures.

Significant Figure Table

Number	Significant Figures
53	2
1011	4
20.9	3
0.0031	2
12.000	5
3450000	3 (if no decimal)

Rules for Calculations

• Addition/Subtraction: Result has as many decimal places as the measurement with the fewest decimal places.

• Multiplication/Division: Result has as many significant figures as the measurement with the fewest significant figures.

Rounding

• If the digit to be dropped is less than 5, leave the last retained digit unchanged.

• If the digit is 5 or greater, increase the last retained digit by 1.

• Do not round until the final step in multi-step calculations.

Scientific Notation

• General form: $c \times 10^n$ where $1 \leq c < 10$ and $n$ is an integer.

• Positive exponent: number greater than 1; negative exponent: number between 0 and 1.

• Only significant figures are shown in the coefficient.

Percent Calculations

• Percent (%) = $\frac{\text{part}}{\text{whole}} \times 100$

• Used to compare quantities of different total sizes.

Properties of Matter

Mass and Weight

• Mass: Amount of material in an object (measured in grams).

• Weight: Force of gravity on an object; varies with location.

Volume

• Space occupied by matter; measured in liters (L) or milliliters (mL).

• 1 mL = 1 cm3 (cubic centimeter)

Density

• Density ($d$) is mass per unit volume: $d = \frac{m}{V}$

• Units: g/mL or g/cm3

• Density of water at 4°C is 1.00 g/mL.

Specific Gravity

• Ratio of the density of a sample to the density of water.

• Specific gravity = $\frac{\text{density of sample}}{\text{density of water}}$

• Unitless quantity.

Temperature Scales

• Fahrenheit (°F): Used in the US.

• Celsius (°C): Used worldwide and in science.

• Kelvin (K): SI unit; absolute scale.

Temperature Conversion Formulas

• Kelvin: $K = °C + 273$

• Celsius: $°C = \frac{5}{9}(°F - 32)$

• Fahrenheit: $°F = (°C \times \frac{9}{5}) + 32$

Body Temperature and Health

• Normal body temperature: 98.6°F (37.0°C)

• Hyperthermia: >40.0°C (104°F)

• Hypothermia: <35.0°C (95°F)

Energy and Heat

• Energy: Capacity to do work or supply heat.

• Potential energy: Stored energy.

• Kinetic energy: Energy of motion.

• Law of Conservation of Energy: Energy is never created or destroyed.

• SI unit: joule (J); 1 calorie (cal) = 4.184 J; 1 Calorie (Cal) = 1000 cal.

Specific Heat

• Amount of heat needed to raise the temperature of 1 g of a substance by 1°C.

• Formula: $\text{Specific heat (SH)} = \frac{\text{heat}}{\text{mass} \times \Delta T}$

• Water has a high specific heat; metals have low specific heat.

Specific Heat Table (Selected Substances)

Substance	Specific Heat (cal/g·°C)
Water	1.00
Human body	0.83
Paraffin wax	0.50
Iron	0.11
Copper	0.092
Gold	0.030

States of Matter

Solid, Liquid, Gas

Property	Solid	Liquid	Gas
Shape	Definite	Adopts container shape	Adopts container shape
Volume	Definite	Definite	Indefinite
Particle arrangement	Closely packed	Loosely packed	Very far apart
Particle interaction	Very strong	Strong	Practically none

Measuring Matter: Accuracy and Precision

Accuracy vs. Precision

• Accuracy: How close a measurement is to the true value.

• Precision: How close repeated measurements are to each other.

• Best practice: Take several measurements and average them.

Measurement in Health and Medicine

Common Units and Conversions

US Customary Unit	SI/Metric Equivalent
Pound (lb)	0.454 kg
Ounce (oz)	28.35 g
Teaspoon (tsp)	5 mL
Tablespoon (tbsp)	15 mL

Dosage Calculations

• Determine the units for the final answer.

• Identify the given information and conversion factors.

• Set up the equation so all units cancel except the desired unit.

Drip Rates

• Measured in drops per milliliter (gtt/mL).

• Drip factor depends on IV tubing diameter.

Percent in Health

• Active ingredient: Binders may be added to pills to increase size.

• Children often receive a percent of the adult dose based on weight.

• Nutrition labels show % Daily Value (%DV) for nutrients.

Additional info: Some context and examples were expanded for clarity and completeness, as is standard in academic study guides.