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Pre-IB/Pre-AP CHEMISTRY. Chapter 2 – Measurements and Calculations. Section 1: Scientific Method. _____________ is a process whose goal is to discover facts about the universe. Most scientific advances result form carefully planned ____________________.
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Pre-IB/Pre-AP CHEMISTRY Chapter 2 – Measurements and Calculations
Section 1: Scientific Method • _____________ is a process whose goal is to discover facts about the universe. • Most scientific advances result form carefully planned ____________________. • Science relies on observation, experimentation, and experience
Section 1: Scientific Method • Scienceis a process whose goal is to discover facts about the universe. • Most scientific advances result form carefully planned investigations. • Science relies on observation, experimentation, and experience
Section 1: Scientific Method • The process researches use to carry out their investigations is called the _________ ________ . • This is a a logical approach to solving problems by ______________ and ______________ _______, ________________ ____________, _______________ hypotheses and formulating ________________ that are supported by data. • The scientific method is ___________________, repeatable and testable.
Section 1: Scientific Method • The process researches use to carry out their investigations is called the scientificmethod. • This is a a logical approach to solving problems by ______________ and ______________ _______, ________________ ____________, _______________ hypotheses and formulating ________________ that are supported by data. • The scientific method is ___________________, repeatable and testable.
Section 1: Scientific Method • The process researches use to carry out their investigations is called the scientificmethod. • This is a a logical approach to solving problems by observingand collectingdata, formulatinghypotheses, testinghypotheses and formulating theories that are supported by data. • The scientific method is ___________________, repeatable and testable.
Section 1: Scientific Method • The process researches use to carry out their investigations is called the scientific method. • This is a a logical approach to solving problems by observingand collecting data, formulating hypotheses, testinghypotheses and formulating theories that are supported by data. • The scientific method issystematic, repeatable and testable.
Section 1: Scientific Method I. Observing and Collecting Data • __________________ – the use of the senses to obtain information. Observation involves making measurements and collecting data. • Two types of data: • ________________– descriptive in nature; _____-_____________ information (ex. the sky is blue) • _________________ - __________________ in nature; (ex. 5 meters long)
Section 1: Scientific Method I. Observing and Collecting Data • Observing– the use of the senses to obtain information. Observation involves making measurements and collecting data. • Two types of data: • ________________– descriptive in nature; _____-_____________ information (ex. the sky is blue) • _________________ - __________________ in nature; (ex. 5 meters long)
Section 1: Scientific Method I. Observing and Collecting Data • Observing– the use of the senses to obtain information. Observation involves making measurements and collecting data. • Two types of data: • Qualitative– descriptive in nature; non-numericalinformation (ex. the sky is blue) • _________________ - __________________ in nature; (ex. 5 meters long)
Section 1: Scientific Method I. Observing and Collecting Data • Observing– the use of the senses to obtain information. Observation involves making measurements and collecting data. • Two types of data: • Qualitative– descriptive in nature; non-numericalinformation (ex. the sky is blue) • Quantitative – numericalin nature; (ex. 5 meters long)
Section 1: Scientific Method I. Observing and Collecting Data • Experimenting involves carrying out a procedure under controlled __________________ to make observations and collect data. • Chemists study ________________ – a specific portion of matter in a given region of space that has been selected for ___________ during an experiment or observation.
Section 1: Scientific Method I. Observing and Collecting Data • Experimenting involves carrying out a procedure under controlledconditionsto make observations and collect data. • Chemists study ________________ – a specific portion of matter in a given region of space that has been selected for ___________ during an experiment or observation.
Section 1: Scientific Method I. Observing and Collecting Data • Experimenting involves carrying out a procedure under controlledconditionsto make observations and collect data. • Chemists study systems– a specific portion of matter in a given region of space that has been selected for study during an experiment or observation.
Section 1: Scientific Method II. Formulating Hypotheses • Scientists examine and compare data from their experiments to attempt to find relationships and ______________ – they try to make generalizations based on the data. • ___________________ -statements that apply to a ___________ of information. Data is sometimes organized into tables and analyzed using statistics/mathematical techniques.
Section 1: Scientific Method II. Formulating Hypotheses • Scientists examine and compare data from their experiments to attempt to find relationships and patterns– they try to make generalizations based on the data. • ___________________ -statements that apply to a ___________ of information. Data is sometimes organized into tables and analyzed using statistics/mathematical techniques.
Section 1: Scientific Method II. Formulating Hypotheses • Scientists examine and compare data from their experiments to attempt to find relationships and patterns– they try to make generalizations based on the data. • Generalizations-statements that apply to a rangeof information. Data is sometimes organized into tables and analyzed using statistics/mathematical techniques.
Section 1: Scientific Method II. Formulating Hypotheses • Scientists then use these generalizations to formulate a ________________ – a testable statement; _________________ __________. The hypothesis serves as basis for making ________________ and for carrying out further experiments. • Hypotheses are often “___ - _________” statements – the “then” part is a prediction that is the basis for testing by experiment.
Section 1: Scientific Method II. Formulating Hypotheses • Scientists then use these generalizations to formulate a hypothesis– a testable statement; an educatedguess. The hypothesis serves as basis for making predictions and for carrying out further experiments. • Hypotheses are often “___ - _________” statements – the “then” part is a prediction that is the basis for testing by experiment.
Section 1: Scientific Method II. Formulating Hypotheses • Scientists then use these generalizations to formulate a hypothesis– a testable statement; an educatedguess. The hypothesis serves as basis for making predictions and for carrying out further experiments. • Hypotheses are often “if- then” statements – the “then” part is a prediction that is the basis for testing by experiment.
Section 1: Scientific Method III. Testing Hypotheses • Testing a hypothesis requires _____________________ that provides data to ____________ or ___________ a hypothesis or theory. • If testing reveals that predictions were NOT correct, the hypothesis must be ______________ or _____________. • Hypotheses can be proven ______________ and they can be supported/proven ______________, but they CANNOT be proven correct.
Section 1: Scientific Method III. Testing Hypotheses • Testing a hypothesis requires experimentationthat provides data to support or refutea hypothesis or theory. • If testing reveals that predictions were NOT correct, the hypothesis must be ______________ or _____________. • Hypotheses can be proven ______________ and they can be supported/proven ______________, but they CANNOT be proven correct.
Section 1: Scientific Method III. Testing Hypotheses • Testing a hypothesis requires experimentationthat provides data to supportor refutea hypothesis or theory. • If testing reveals that predictions were NOT correct, the hypothesis must be discardedor modified. • Hypotheses can be proven ______________ and they can be supported/proven ______________, but they CANNOT be proven correct.
Section 1: Scientific Method III. Testing Hypotheses • Testing a hypothesis requires experimentationthat provides data to supportor refutea hypothesis or theory. • If testing reveals that predictions were NOT correct, the hypothesis must be discardedor modified. • Hypotheses can be proven incorrectand they can be supported/proven successful, but they CANNOT be proven correct.
Section 1: Scientific Method III. Testing Hypotheses • ____________ – Experimental conditions that remain ______________ during testing. • ______________ – any conditions that __________ during testing. • Any changes observed are due to the effects of the variable. • Might affect the outcome of the experiment
Section 1: Scientific Method III. Testing Hypotheses • Controls – Experimental conditions that remain constantduring testing. • ______________ – any conditions that __________ during testing. • Any changes observed are due to the effects of the variable. • Might affect the outcome of the experiment
Section 1: Scientific Method III. Testing Hypotheses • Controls – Experimental conditions that remain constantduring testing. • Variables – any conditions that change during testing. • Any changes observed are due to the effects of the variable. • Might affect the outcome of the experiment
Section 1: Scientific Method III. Testing Hypotheses • Two types of variables: • _______________ - the variable that is manipulated by the experimenter. There should only be ______ in an experiment. • _______________ - variable that is studied. It is expected to change as a result of changes in the ________________ variable. There may be more than one dependent variable.
Section 1: Scientific Method III. Testing Hypotheses • Two types of variables: • Independent- the variable that is manipulated by the experimenter. There should only be ONEin an experiment. • _______________ - variable that is studied. It is expected to change as a result of changes in the ________________ variable. There may be more than one dependent variable.
Section 1: Scientific Method III. Testing Hypotheses • Two types of variables: • Independent- the variable that is manipulated by the experimenter. There should only be ONEin an experiment. • Dependent- variable that is studied. It is expected to change as a result of changes in the independentvariable. There may be more than one dependent variable.
Section 1: Scientific Method III. Testing Hypotheses Two groups: Controlgroup - allows you to observe what is considered “normal” under a specific set of conditions, so comparisons can be made with the experimental group. Experimentalgroup – this group experiences a change in onevariable. Only one variable should be changed at a time
Section 1: Scientific Method IV. Theorizing • When data shows that the predictions of a hypothesis are successful, scientist then typically try to explain the phenomena they are studying by constructing a ___________– more than just a physical object, it is often an ____________________ of how phenomena occur and how data or events are _____________. • Models may be _____________, verbal or _____________________.
Section 1: Scientific Method IV. Theorizing • When data shows that the predictions of a hypothesis are successful, scientist then typically try to explain the phenomena they are studying by constructing a model– more than just a physical object, it is often an explanationof how phenomena occur and how data or events are related. • Models may be _____________, verbal or _____________________.
Section 1: Scientific Method IV. Theorizing • When data shows that the predictions of a hypothesis are successful, scientist then typically try to explain the phenomena they are studying by constructing a model– more than just a physical object, it is often an explanationof how phenomena occur and how data or events are related. • Models may be visual, verbal or mathematical. • Ex. Atomic model of matter – states that matter is composed of tiny particles – atoms
Section 1: Scientific Method IV. Theorizing • ______________– a broad generalization that explains a body of facts or phenomena. • If a model successfully explains many phenomena, it may become part of a theory. • Theories are considered successful if they can ___________ the ___________ of many new experiments.
Section 1: Scientific Method IV. Theorizing • Theory– a broad generalization that explains a body of facts or phenomena. • If a model successfully explains many phenomena, it may become part of a theory. • Theories are considered successful if they can ___________ the ___________ of many new experiments.
Section 1: Scientific Method IV. Theorizing • Theory– a broad generalization that explains a body of facts or phenomena. • If a model successfully explains many phenomena, it may become part of a theory. • Theories are considered successful if they can predict the results of many new experiments.
Section 1: Scientific Method IV. Theorizing • Theory– a broad generalization that explains a body of facts or phenomena. • Ex. Kinetic-Molecular Theory – Theory that explains that the behavior of physical systems depends on the combined actions of the molecules constituting the system • Ex. Collision Theory – Theory that states that the number of new compounds formed in a chemical reaction is = to the number of molecules that collide
Section 1: Scientific Method IV. Theorizing • ___________________ gives scientists an opportunity to ______________ the work of others and see if they get the _________ _______________. • Others will be able to duplicate valid work.
Section 1: Scientific Method IV. Theorizing • Publicationgives scientists an opportunity to repeat the work of others and see if they get the sameresults. • Others will be able to duplicate valid work.
Section 1: Scientific Method Question Research Hypothesis Experiment Analysis Conclusion
Section 2 Objectives • Be able to define: quantity, measurement, standard, length, mass, weight, derived unit, volume, density, conversion factor. • Be able to state the units of mass, length, temperature, and time in the SI system.
Section 2 Objectives • Be able to explain the difference between mass and weight. • Be able to state the meaning of common prefixes used in the SI system (Deka-, Hecto-, Kilo-, Mega-, Giga-, deci-, centi-, milli-, micro-, nano-. • Be able to convert units within the SI system.
Measurement • Measurements represent quantities. • A quantity is something that has magnitude, size, or amount.
Measurement • Measurements and quantities are not the same. Example: A teaspoon is a unit of measurement for volume (a quantity).
Units of Measurement • Units of measurement vary from place to place. Using all of them would lead to confusion in reporting scientific investigations.
SI System • In 1960, scientists agreed to use Le Système International d’Unitésor the SI system of measurement.
SI System • The SI system defines 7 base units for length, mass, time, temperature, amount of a substance, etc.
Standards • The SI system defined standards for every base unit that can be replicated (Table 1, Pg. 34).