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Chemistry is the science that investigates and explains the structure and properties of matter. Chemistry and Matter: Basic Concepts Matter is anything that takes up space and has mass. Chapter 1 Chapter 1
Mass is the measure of the amount of matter that an object contains. Mass is a measure of inertia. The properties of matter describe the characteristics and behavior of matter, including the changes that matter undergoes. Chapter 1 Chapter 1 Chemistry and Matter: Basic Concepts Mass vs. weight
Matter that is large enough to be seen is called macroscopic. Chapter 1 Chapter 1 Chemistry and Matter: Basic Concepts The submicroscopic view gives you a glimpse into the world of atoms.
Chemistry and Matter: Additional Concepts Branches of Chemistry BranchArea of Emphasis Examples Organic chemistry most carbon-containing chemicalspharmaceuticals, plastics Inorganic chemistry in general, matter that does not contain carbon minerals, metals and nonmetals, semi- conductors Physical chemistry the behavior and changes of matter and the related energy changes reaction rates, reaction mechanisms Analytical chemistry components and composition of substances food nutrients, quality control Biochemistrymatter and processes of living organisms metabolism, fermentation Chapter 1 Chapter 1
See figure 1-9 page 11. Scientific Methods Qualitative data vs. quantitative data Independent variable vs. dependent variable Chapter 1 Chapter 1 Chemistry and Matter: Basic Concepts A quantitative observation is one that uses measurement. A qualitative observation is one that can be made without measurement.
Scientific Methods The variable that is changed in an experiment is called the independent variable. The variable that you watch to see how it changes as a result of your changes to the independent variable is called the dependent variable. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts
Scientific Research Pure research is done to gain knowledge for the sake of knowledge itself. Applied research is undertaken to solve a specific problem. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts
Scientific Methods A typical scientific method includes: making observations, forming a hypothesis, performing an experiment, and arriving at a conclusion. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts
Scientific Methods Many experiments also include a control, which is a standard for comparison. A conclusion is a judgment based on the data obtained in the experiment. If data support a hypothesis, the hypothesis is tentatively affirmed. Hypotheses are never proven; they are always subject to additional research. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts
Scientific Methods Over time, data from many experiments can be used to form a visual, verbal, and/or mathematical explanation—called a model—of the phenomenon being studied. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts A theory is an explanation that has been supported by many experiments. Theories are always subject to new experimental data and are modified to include new data.
A scientific model is a thinking device that helps you understand and explain macroscopic observations. Scientific models are built on experimentation. Using Models in Chemistry Chapter 1 Chapter 1 Chemistry and Matter: Basic Concepts
Scientific Methods Often, a scientist will begin with qualitative data—information that describes color, odor, shape, or some other physical characteristic that relates to the five senses. Chemists also use numerical quantitative data. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts A hypothesis is a possible explanation for what has been observed. An experiment is a set of controlled observations that test a hypothesis.
Scientific Methods Over time, data from many experiments can be used to form a visual, verbal, and/or mathematical explanation—called a model—of the phenomenon being studied. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts A theory is an explanation that has been supported by many experiments. Theories are always subject to new experimental data and are modified to include new data.
Scientific Methods A scientific law describes a relationship in nature that is supported by many experiments and for which no exception has been found. Chapter 1 Chapter 1 Chemistry and Matter: Additional Concepts
Additional Assessment Questions Identify the dependent variable and the independent variable in the following experiments. Question 1 Chapter 1 Chapter 1
A student tests the ability of a given chemical to dissolve in water at three different temperatures. independent variable: temperature; dependent variable: ability to dissolve in water Answer 1a Question 1a Chapter 1 Chapter 1 Additional Assessment Questions
A farmer compares how his crops grow with and without phosphorous fertilizers. independent variable: presence of phosphorous fertilizer; dependent variable: crop growth Answer 1b Question 1b Chapter 1 Chapter 1 Additional Assessment Questions
Classify each kind of research as either pure or applied. Question 2 chapter 1 chapter 1 Additional Assessment Questions
A scientist studies plants in a rain forest in search of chemicals that might be used to treat AIDS. applied Answer 2a Question 2a chapter 1 chapter 1 Additional Assessment Questions
A researcher studies the effects of hormones on the brain of a worm. pure Answer 2b Question 2b chapter 1 chapter 1 Additional Assessment Questions
A researcher tries to develop cleaner burning fuels to help reduce air pollution. applied Answer 2c Question 2c chapter 1 chapter 1 Additional Assessment Questions