BackCH107: Chemistry in Our Lives – Study Notes (Chapter 1 & Math Skills)
Study Guide - Smart Notes
Tailored notes based on your materials, expanded with key definitions, examples, and context.
Chemistry in Our Lives
Introduction to Chemistry
Chemistry is the study of the composition, structure, properties, and reactions of matter. It is a central science that connects to many fields, including biology, medicine, pharmacology, and environmental science. Understanding chemistry helps explain processes at the molecular level in the human body and supports safe medication administration, patient monitoring, and many real-world applications.
Chemistry happens all around us every day.
Examples: Antacid tablets undergo a chemical reaction when dropped in water.
What is a Chemical?
A chemical is a substance that has the same composition and properties regardless of where it is found. For example, water (H2O) is always composed of hydrogen and oxygen in a 2:1 ratio, whether it is found in a river or in a laboratory.
Chemistry and Matter
Matter is another word for all substances that make up our world. Matter is defined as anything that has mass and occupies space (volume).
Examples of matter: Antacid tablets, water, glass, air.
The Scientific Method in Chemistry
Scientists and Scientific Thinking
Chemists, biochemists, biologists, and researchers use a scientific approach similar to detectives, using the scientific method to solve puzzles and answer questions. The scientific method is a process for experimentation that is used to explore observations and answer questions.
Scientists ask questions such as: Why do certain cancer cells spread faster? How do we recall memories? How can we treat bacterial infections?
The Scientific Method Steps
Observe: Make observations about the world.
Question: Ask a question or identify a problem.
Research: Gather information and resources.
Hypothesize: Formulate a hypothesis (a testable explanation).
Experiment: Test the hypothesis with experiments.
Test Hypothesis: Analyze results and draw conclusions.
Report: Share findings.
Example: Using the Scientific Method in Daily Life
If your alarm clock does not go off, you might hypothesize possible reasons (power failure, someone turned it off, or you forgot to set it). By investigating, you find the answer, demonstrating the use of the scientific method in problem-solving.
Types of Scientific Statements
Observation: Directly recorded data (e.g., "You ran for 25 minutes on the treadmill").
Theory: Broad explanation supported by evidence (e.g., "Exercising lowers blood pressure").
Hypothesis: Testable explanation (e.g., "Weight loss is due to increased exercise").
Essential Math Skills for Chemistry
Overview
CH107 focuses on simple algebra, dimensional analysis (correct use of units and conversions), ratio and proportion, and solving for a single variable in an equation. These skills are essential for medication dosage calculations, fluid balance, and interpreting clinical data.
Identifying Place Values
Each digit in a number has a specific place value, which is important for understanding measurements and calculations.
Digit | Place Value (2518) | Place Value (6.407) |
|---|---|---|
2 | Thousands | |
5 | Hundreds | |
1 | Tens | |
8 | Ones | |
6 | Ones | |
4 | Tenths | |
0 | Hundredths | |
7 | Thousandths |
Calculations Using Positive and Negative Numbers
Understanding how to add, subtract, multiply, and divide positive and negative numbers is crucial for clinical calculations, such as fluid balance assessments.
Fluid balance = total input (mL) - total output (mL)
Positive and negative numbers are used to represent gains and losses.
Solving Simple Equations
An equation is a mathematical statement that shows two expressions are equal. In chemistry and healthcare, equations are used to solve for unknowns, such as medication dosages or fluid rates.
Steps to solve equations:
Place all like items on one side.
Isolate the variable you need to solve for.
Check your answer.
Example: Subtract 8: Divide by 2:
Utility of Solving Equations in Health Care
Medication Dosage Calculation: Use of ratios and proportions to determine doses.
IV Drip Rates: Calculating fluid volume per hour and drops per minute.
Weight & Volume Conversions: Converting between units (e.g., pounds to kilograms).
Equipment & Monitoring: Interpreting clinical device data.
Fluid & Electrolyte Balance: Calculating intake and output.
Charts and Plots in Chemistry and Medicine
Why Use Charts and Plots?
Visualize data for better comprehension.
Summarize large datasets, highlight trends, and compare variables.
Support clinical decision-making and error prevention.
Enhance communication and patient engagement.
General Steps in Interpreting a Graph
Note labels for axes, range of values, and units.
Interpret the plotted data and any error bars.
Example: Converting Celsius to Fahrenheit:
Percentages in Chemistry and Healthcare
Definition and Use
Percent means "per 100." Percentages are used in medication concentrations, assessments, and calculations.
Example: Magnesium sulfate 50% solution.
Converting Between Fractions, Decimals, and Percents
Conversion | Steps | Example |
|---|---|---|
Percent to Fraction | Write as fraction over 100, simplify | 36% = 36/100 = 9/25 |
Percent to Decimal | Divide by 100 | 6% = 6/100 = 0.06 |
Decimal to Percent | Multiply by 100 | 0.4 = 40% |
Fraction to Percent | Convert to decimal, multiply by 100 | 3/4 = 0.75 = 75% |
Scientific Notation
Purpose and Rules
Scientific notation is used to express very large or very small numbers conveniently and to report the correct number of significant digits.
Numbers in scientific notation have two parts: a coefficient and a power of 10.
Writing Numbers in Scientific Notation
Move the decimal point so that only one nonzero digit is to the left.
Count the number of places moved; this is the exponent on 10.
If the decimal is moved to the left, the exponent is positive; if to the right, it is negative.
Example (number greater than 10):
Example (number less than 1):
Practice Problems
Write 64,000 in scientific notation:
Write 0.021 in scientific notation:
Study Tips for Chemistry
Read textbook chapters and lecture slides before class.
Practice problems regularly, not just before exams.
Use office hours and seek help early if needed.
Summarize notes and use flashcards for key terms and math skills.
Additional info: These notes are based on the first chapter and introductory math skills for a General, Organic, and Biological Chemistry (GOB Chemistry) course, suitable for students in health and life sciences.
